Download - Bitcoin

Support page for Kraken Digital Assets Exchange

Support page for Kraken Digital Assets Exchange
[link]

Secure PoS Terminal Bitcoin-client with double spend detection?

Anyone have seen such implementation that I can run myself? http://blockchain.info/api/api_receive is more or less what I'm after but with the added "watch the network for double spends" feature.
The flow and rules will be like this:
Notifications must be raised for new transactions with any receive address that we watch for, as well as any tx inputs (double spends) that have been seen in any such transactions, and the coming 6 blocks for those transactions.
Edit: fix formatting.
submitted by nikize to BitcoinDevelopers [link] [comments]

If you need help or you're New to roms and emulation these are some tips

First thing first You need an Emulator i suggest RetroArch is a Newbie Friendly good all in one emulator this is a video to how to setup and use ReTrOaRcH
OpenEmu FOR MAC USERS THAT WILL NOT USE RETRO ARCH BECAUSE IT'S NOT ENOUGH LOOKING LIKE MAC UI OR THEY HAVE AN OCD OR something like that it's good anyways ( i didn't use it bc i'm not a mac user )
🕿︎♋︎◻︎◻︎●︎♏︎ ◻︎❒︎□︎♎︎◆︎♍︎⧫︎⬧︎ ♋︎❒︎♏︎ □︎❖︎♏︎❒︎◻︎❒︎♓︎♍︎♏︎♎︎✆︎
and a download Manger
Jdownloader ( download the jar version ) A photo to explain what to download (don't download the .exe version it has an adware in it )
or idm u can trial reset with this
a torrent clients (credits to Piracy wiki)
for mobile ( torrent clients ) [credits to Piracy wiki]
stay away from [credits to Piracy wiki]
second you need sources to download roms these are the best sites + some tips
sites :
ziperto
No intro romset ( you can download it directly without a torrent you CAN FROM HERE ) (If you don't want to download the whole romset for the system press view content )
AlvRo's Collection
Vimm's Lair
The Eye
GamesTorrents ( of course if u can torrent )
MEGA-ROM
N(itro)blog
THE MEGATHREAD
RomsUniverse
MOBAsuite
IDK?? A WIKI FOR ROMpacks?????
The Old Megathread idk why u need it
A guy who uploaded some roms but he didn't get attention
ROMstorge ( idk how to use this site )
Roms WIKI
Another ROMs site
Edgeemu
EmulatorGames ( the name is baaaaaaaad )
ROMsDownload
WoW Roms
cdROMance
Startgame ( wtf is this name )
Retrostic
ROMulation
If u Want to Check if the site is safe go to here and comment ur site url
Tips :
Tip #1 : If you're in a country that hate piracy like USA or Germany ( i think Germany have dmca or something ?? idk ) etc. stay away from torrent and stay away from http sites
( download Https Everywhere extension and enable encrypt all sites eligible option by pressing on the icon of https everywhere ) even if your browser included with it . because it will warn you if the site is http...
Tip #2 : FBI will not raid your house ( because fbi will not waste there time on you )
Tip #3 : https is your best friend because it's encrypted that means if you go to a https roms site
your isp will see (random numbers and letters) .com/.net/.org/.to/.site etc.
Tip #4 : install an adblock i suggest Ublock Origin
Tip #5 : install a pop-up blocker if you have a chromium based browser like Brave, Chrome, New Edge etc. i suggest this ( if you know a better one please give me the link ) poperblocker
Tip #6 The MegaThread is your OTHER BEST FRIEND if you want an rom head to the megathread and press ctrl + F and search ;)
Tip #7 DON'T DO NOT OPEN ANY ANY ANY .MSI .EXE/.DMG/.DEB or ANY OTHER FILE THAT you CAN OPEN WITHOUT AN EMULATOR THE FILE IT'S 2000% A VIRUS ( EXCEPT WHEN you DOWNLOAD RETRO ARCH [ or any other emulator OF COURSE ] ) AND DON'T OPEN .BAT FILES IT CAN DELETE SYSTEM32 FILE AND IT'S ONE OF THE MOST IMPORTANT FILES IN WINDOWS
Tip #8 Emulating is Legal but Downloading ROMs is ILEGAL ( OF COURSE IF you're LIVING IN A COUNTRY THAT DMCA IS A HOLY THING ) ;-)
Tip #9 If you're suspicious of a file u can scan it on VirusTotal or Hybird Analysis ( you need to upload the file because it will open it on a vm in there sever ).
Tip #10 I recommend using a controller if you have a xbox controller just connect it to your pc and you're good to go BUT if you have a dualshock controller (ps controller )
use DS4 Windows ( if you have a windows pc ) ( I Know it's the fork bc the og creator stopped working on it in 2016 or somthing like that )
or any other controller .
Tip #11 If you download a rom and it came in .rar .zip .7z .r001( if the rom came with multiple files like .r001 .r002 .r003... you need to extract just a one file) etc. you can use 7-ZIP or Winrar ( don't worry 40 days trial doesn't end ).

Tip #12 if the rom came in this order rom.rar.exe don't think to open it and if you hide the extension file from showing from the file name it will show like rom.rar but it's actually a .exe or .dmg etc.

Tip #13 if you have a linux pc or a mac that doesn't mean you will not get infected even Temple OS have malwares ( if you don't what's a malware is just search )​.
Tip #14 if u tired of link shorters and etc. use universal Bypass
Tip #15 Some good emulators :
Dolphin a wii and gamecube emulator ( check the compatibility list to check if the game work )
Citra 3DS emulator ( check the compatibility list to check if the game work )
BSNES HD beta if u want to play snes games on HD
PCSX2 the best ps2 emulator
EPSXE a little bit old but it's good (ps1)
DON'T use zsnes ( i guy on the comments said that )
RPCS3 PS3 ( check the compatibility list to check if the game work )
Xenia Xbox 360 ( check the compatibility list to check if the game work )
Cemu WiiU Emulator ( check the compatibility list to check if the game work )
a Decryptor for 3ds games if citra won't open the rom HERE
DS DeSmuME (OLD) ( if u have a good ds emulator give me the link pls )
Project64 N64
DOSBox DOS emulator ( check the compatibility list to check if the game work )
IF U HAVE any other emulator pls link it in the comments <3
Tip #16
Romsmania
CoolRoms
etc. are NOT SAFE
if you have any other tips share it =)
submitted by real_nyha454 to Roms [link] [comments]

Dragonchain Great Reddit Scaling Bake-Off Public Proposal

Dragonchain Great Reddit Scaling Bake-Off Public Proposal

Dragonchain Public Proposal TL;DR:

Dragonchain has demonstrated twice Reddit’s entire total daily volume (votes, comments, and posts per Reddit 2019 Year in Review) in a 24-hour demo on an operational network. Every single transaction on Dragonchain is decentralized immediately through 5 levels of Dragon Net, and then secured with combined proof on Bitcoin, Ethereum, Ethereum Classic, and Binance Chain, via Interchain. At the time, in January 2020, the entire cost of the demo was approximately $25K on a single system (transaction fees locked at $0.0001/txn). With current fees (lowest fee $0.0000025/txn), this would cost as little as $625.
Watch Joe walk through the entire proposal and answer questions on YouTube.
This proposal is also available on the Dragonchain blog.

Hello Reddit and Ethereum community!

I’m Joe Roets, Founder & CEO of Dragonchain. When the team and I first heard about The Great Reddit Scaling Bake-Off we were intrigued. We believe we have the solutions Reddit seeks for its community points system and we have them at scale.
For your consideration, we have submitted our proposal below. The team at Dragonchain and I welcome and look forward to your technical questions, philosophical feedback, and fair criticism, to build a scaling solution for Reddit that will empower its users. Because our architecture is unlike other blockchain platforms out there today, we expect to receive many questions while people try to grasp our project. I will answer all questions here in this thread on Reddit, and I've answered some questions in the stream on YouTube.
We have seen good discussions so far in the competition. We hope that Reddit’s scaling solution will emerge from The Great Reddit Scaling Bake-Off and that Reddit will have great success with the implementation.

Executive summary

Dragonchain is a robust open source hybrid blockchain platform that has proven to withstand the passing of time since our inception in 2014. We have continued to evolve to harness the scalability of private nodes, yet take full advantage of the security of public decentralized networks, like Ethereum. We have a live, operational, and fully functional Interchain network integrating Bitcoin, Ethereum, Ethereum Classic, and ~700 independent Dragonchain nodes. Every transaction is secured to Ethereum, Bitcoin, and Ethereum Classic. Transactions are immediately usable on chain, and the first decentralization is seen within 20 seconds on Dragon Net. Security increases further to public networks ETH, BTC, and ETC within 10 minutes to 2 hours. Smart contracts can be written in any executable language, offering full freedom to existing developers. We invite any developer to watch the demo, play with our SDK’s, review open source code, and to help us move forward. Dragonchain specializes in scalable loyalty & rewards solutions and has built a decentralized social network on chain, with very affordable transaction costs. This experience can be combined with the insights Reddit and the Ethereum community have gained in the past couple of months to roll out the solution at a rapid pace.

Response and PoC

In The Great Reddit Scaling Bake-Off post, Reddit has asked for a series of demonstrations, requirements, and other considerations. In this section, we will attempt to answer all of these requests.

Live Demo

A live proof of concept showing hundreds of thousands of transactions
On Jan 7, 2020, Dragonchain hosted a 24-hour live demonstration during which a quarter of a billion (250 million+) transactions executed fully on an operational network. Every single transaction on Dragonchain is decentralized immediately through 5 levels of Dragon Net, and then secured with combined proof on Bitcoin, Ethereum, Ethereum Classic, and Binance Chain, via Interchain. This means that every single transaction is secured by, and traceable to these networks. An attack on this system would require a simultaneous attack on all of the Interchained networks.
24 hours in 4 minutes (YouTube):
24 hours in 4 minutes
The demonstration was of a single business system, and any user is able to scale this further, by running multiple systems simultaneously. Our goals for the event were to demonstrate a consistent capacity greater than that of Visa over an extended time period.
Tooling to reproduce our demo is available here:
https://github.com/dragonchain/spirit-bomb

Source Code

Source code (for on & off-chain components as well tooling used for the PoC). The source code does not have to be shared publicly, but if Reddit decides to use a particular solution it will need to be shared with Reddit at some point.

Scaling

How it works & scales

Architectural Scaling

Dragonchain’s architecture attacks the scalability issue from multiple angles. Dragonchain is a hybrid blockchain platform, wherein every transaction is protected on a business node to the requirements of that business or purpose. A business node may be held completely private or may be exposed or replicated to any level of exposure desired.
Every node has its own blockchain and is independently scalable. Dragonchain established Context Based Verification as its consensus model. Every transaction is immediately usable on a trust basis, and in time is provable to an increasing level of decentralized consensus. A transaction will have a level of decentralization to independently owned and deployed Dragonchain nodes (~700 nodes) within seconds, and full decentralization to BTC and ETH within minutes or hours. Level 5 nodes (Interchain nodes) function to secure all transactions to public or otherwise external chains such as Bitcoin and Ethereum. These nodes scale the system by aggregating multiple blocks into a single Interchain transaction on a cadence. This timing is configurable based upon average fees for each respective chain. For detailed information about Dragonchain’s architecture, and Context Based Verification, please refer to the Dragonchain Architecture Document.

Economic Scaling

An interesting feature of Dragonchain’s network consensus is its economics and scarcity model. Since Dragon Net nodes (L2-L4) are independent staking nodes, deployment to cloud platforms would allow any of these nodes to scale to take on a large percentage of the verification work. This is great for scalability, but not good for the economy, because there is no scarcity, and pricing would develop a downward spiral and result in fewer verification nodes. For this reason, Dragonchain uses TIME as scarcity.
TIME is calculated as the number of Dragons held, multiplied by the number of days held. TIME influences the user’s access to features within the Dragonchain ecosystem. It takes into account both the Dragon balance and length of time each Dragon is held. TIME is staked by users against every verification node and dictates how much of the transaction fees are awarded to each participating node for every block.
TIME also dictates the transaction fee itself for the business node. TIME is staked against a business node to set a deterministic transaction fee level (see transaction fee table below in Cost section). This is very interesting in a discussion about scaling because it guarantees independence for business implementation. No matter how much traffic appears on the entire network, a business is guaranteed to not see an increased transaction fee rate.

Scaled Deployment

Dragonchain uses Docker and Kubernetes to allow the use of best practices traditional system scaling. Dragonchain offers managed nodes with an easy to use web based console interface. The user may also deploy a Dragonchain node within their own datacenter or favorite cloud platform. Users have deployed Dragonchain nodes on-prem on Amazon AWS, Google Cloud, MS Azure, and other hosting platforms around the world. Any executable code, anything you can write, can be written into a smart contract. This flexibility is what allows us to say that developers with no blockchain experience can use any code language to access the benefits of blockchain. Customers have used NodeJS, Python, Java, and even BASH shell script to write smart contracts on Dragonchain.
With Docker containers, we achieve better separation of concerns, faster deployment, higher reliability, and lower response times.
We chose Kubernetes for its self-healing features, ability to run multiple services on one server, and its large and thriving development community. It is resilient, scalable, and automated. OpenFaaS allows us to package smart contracts as Docker images for easy deployment.
Contract deployment time is now bounded only by the size of the Docker image being deployed but remains fast even for reasonably large images. We also take advantage of Docker’s flexibility and its ability to support any language that can run on x86 architecture. Any image, public or private, can be run as a smart contract using Dragonchain.

Flexibility in Scaling

Dragonchain’s architecture considers interoperability and integration as key features. From inception, we had a goal to increase adoption via integration with real business use cases and traditional systems.
We envision the ability for Reddit, in the future, to be able to integrate alternate content storage platforms or other financial services along with the token.
  • LBRY - To allow users to deploy content natively to LBRY
  • MakerDAO to allow users to lend small amounts backed by their Reddit community points.
  • STORJ/SIA to allow decentralized on chain storage of portions of content. These integrations or any other are relatively easy to integrate on Dragonchain with an Interchain implementation.

Cost

Cost estimates (on-chain and off-chain) For the purpose of this proposal, we assume that all transactions are on chain (posts, replies, and votes).
On the Dragonchain network, transaction costs are deterministic/predictable. By staking TIME on the business node (as described above) Reddit can reduce transaction costs to as low as $0.0000025 per transaction.
Dragonchain Fees Table

Getting Started

How to run it
Building on Dragonchain is simple and requires no blockchain experience. Spin up a business node (L1) in our managed environment (AWS), run it in your own cloud environment, or on-prem in your own datacenter. Clear documentation will walk you through the steps of spinning up your first Dragonchain Level 1 Business node.
Getting started is easy...
  1. Download Dragonchain’s dctl
  2. Input three commands into a terminal
  3. Build an image
  4. Run it
More information can be found in our Get started documents.

Architecture
Dragonchain is an open source hybrid platform. Through Dragon Net, each chain combines the power of a public blockchain (like Ethereum) with the privacy of a private blockchain.
Dragonchain organizes its network into five separate levels. A Level 1, or business node, is a totally private blockchain only accessible through the use of public/private keypairs. All business logic, including smart contracts, can be executed on this node directly and added to the chain.
After creating a block, the Level 1 business node broadcasts a version stripped of sensitive private data to Dragon Net. Three Level 2 Validating nodes validate the transaction based on guidelines determined from the business. A Level 3 Diversity node checks that the level 2 nodes are from a diverse array of locations. A Level 4 Notary node, hosted by a KYC partner, then signs the validation record received from the Level 3 node. The transaction hash is ledgered to the Level 5 public chain to take advantage of the hash power of massive public networks.
Dragon Net can be thought of as a “blockchain of blockchains”, where every level is a complete private blockchain. Because an L1 can send to multiple nodes on a single level, proof of existence is distributed among many places in the network. Eventually, proof of existence reaches level 5 and is published on a public network.

API Documentation

APIs (on chain & off)

SDK Source

Nobody’s Perfect

Known issues or tradeoffs
  • Dragonchain is open source and even though the platform is easy enough for developers to code in any language they are comfortable with, we do not have so large a developer community as Ethereum. We would like to see the Ethereum developer community (and any other communities) become familiar with our SDK’s, our solutions, and our platform, to unlock the full potential of our Ethereum Interchain. Long ago we decided to prioritize both Bitcoin and Ethereum Interchains. We envision an ecosystem that encompasses different projects to give developers the ability to take full advantage of all the opportunities blockchain offers to create decentralized solutions not only for Reddit but for all of our current platforms and systems. We believe that together we will take the adoption of blockchain further. We currently have additional Interchain with Ethereum Classic. We look forward to Interchain with other blockchains in the future. We invite all blockchains projects who believe in decentralization and security to Interchain with Dragonchain.
  • While we only have 700 nodes compared to 8,000 Ethereum and 10,000 Bitcoin nodes. We harness those 18,000 nodes to scale to extremely high levels of security. See Dragonchain metrics.
  • Some may consider the centralization of Dragonchain’s business nodes as an issue at first glance, however, the model is by design to protect business data. We do not consider this a drawback as these nodes can make any, none, or all data public. Depending upon the implementation, every subreddit could have control of its own business node, for potential business and enterprise offerings, bringing new alternative revenue streams to Reddit.

Costs and resources

Summary of cost & resource information for both on-chain & off-chain components used in the PoC, as well as cost & resource estimates for further scaling. If your PoC is not on mainnet, make note of any mainnet caveats (such as congestion issues).
Every transaction on the PoC system had a transaction fee of $0.0001 (one-hundredth of a cent USD). At 256MM transactions, the demo cost $25,600. With current operational fees, the same demonstration would cost $640 USD.
For the demonstration, to achieve throughput to mimic a worldwide payments network, we modeled several clients in AWS and 4-5 business nodes to handle the traffic. The business nodes were tuned to handle higher throughput by adjusting memory and machine footprint on AWS. This flexibility is valuable to implementing a system such as envisioned by Reddit. Given that Reddit’s daily traffic (posts, replies, and votes) is less than half that of our demo, we would expect that the entire Reddit system could be handled on 2-5 business nodes using right-sized containers on AWS or similar environments.
Verification was accomplished on the operational Dragon Net network with over 700 independently owned verification nodes running around the world at no cost to the business other than paid transaction fees.

Requirements

Scaling

This PoC should scale to the numbers below with minimal costs (both on & off-chain). There should also be a clear path to supporting hundreds of millions of users.
Over a 5 day period, your scaling PoC should be able to handle:
*100,000 point claims (minting & distributing points) *25,000 subscriptions *75,000 one-off points burning *100,000 transfers
During Dragonchain’s 24 hour demo, the above required numbers were reached within the first few minutes.
Reddit’s total activity is 9000% more than Ethereum’s total transaction level. Even if you do not include votes, it is still 700% more than Ethereum’s current volume. Dragonchain has demonstrated that it can handle 250 million transactions a day, and it’s architecture allows for multiple systems to work at that level simultaneously. In our PoC, we demonstrate double the full capacity of Reddit, and every transaction was proven all the way to Bitcoin and Ethereum.
Reddit Scaling on Ethereum

Decentralization

Solutions should not depend on any single third-party provider. We prefer solutions that do not depend on specific entities such as Reddit or another provider, and solutions with no single point of control or failure in off-chain components but recognize there are numerous trade-offs to consider
Dragonchain’s architecture calls for a hybrid approach. Private business nodes hold the sensitive data while the validation and verification of transactions for the business are decentralized within seconds and secured to public blockchains within 10 minutes to 2 hours. Nodes could potentially be controlled by owners of individual subreddits for more organic decentralization.
  • Billing is currently centralized - there is a path to federation and decentralization of a scaled billing solution.
  • Operational multi-cloud
  • Operational on-premises capabilities
  • Operational deployment to any datacenter
  • Over 700 independent Community Verification Nodes with proof of ownership
  • Operational Interchain (Interoperable to Bitcoin, Ethereum, and Ethereum Classic, open to more)

Usability Scaling solutions should have a simple end user experience.

Users shouldn't have to maintain any extra state/proofs, regularly monitor activity, keep track of extra keys, or sign anything other than their normal transactions
Dragonchain and its customers have demonstrated extraordinary usability as a feature in many applications, where users do not need to know that the system is backed by a live blockchain. Lyceum is one of these examples, where the progress of academy courses is being tracked, and successful completion of courses is rewarded with certificates on chain. Our @Save_The_Tweet bot is popular on Twitter. When used with one of the following hashtags - #please, #blockchain, #ThankYou, or #eternalize the tweet is saved through Eternal to multiple blockchains. A proof report is available for future reference. Other examples in use are DEN, our decentralized social media platform, and our console, where users can track their node rewards, view their TIME, and operate a business node.
Examples:

Transactions complete in a reasonable amount of time (seconds or minutes, not hours or days)
All transactions are immediately usable on chain by the system. A transaction begins the path to decentralization at the conclusion of a 5-second block when it gets distributed across 5 separate community run nodes. Full decentralization occurs within 10 minutes to 2 hours depending on which interchain (Bitcoin, Ethereum, or Ethereum Classic) the transaction hits first. Within approximately 2 hours, the combined hash power of all interchained blockchains secures the transaction.

Free to use for end users (no gas fees, or fixed/minimal fees that Reddit can pay on their behalf)
With transaction pricing as low as $0.0000025 per transaction, it may be considered reasonable for Reddit to cover transaction fees for users.
All of Reddit's Transactions on Blockchain (month)
Community points can be earned by users and distributed directly to their Reddit account in batch (as per Reddit minting plan), and allow users to withdraw rewards to their Ethereum wallet whenever they wish. Withdrawal fees can be paid by either user or Reddit. This model has been operating inside the Dragonchain system since 2018, and many security and financial compliance features can be optionally added. We feel that this capability greatly enhances user experience because it is seamless to a regular user without cryptocurrency experience, yet flexible to a tech savvy user. With regard to currency or token transactions, these would occur on the Reddit network, verified to BTC and ETH. These transactions would incur the $0.0000025 transaction fee. To estimate this fee we use the monthly active Reddit users statista with a 60% adoption rate and an estimated 10 transactions per month average resulting in an approximate $720 cost across the system. Reddit could feasibly incur all associated internal network charges (mining/minting, transfer, burn) as these are very low and controllable fees.
Reddit Internal Token Transaction Fees

Reddit Ethereum Token Transaction Fees
When we consider further the Ethereum fees that might be incurred, we have a few choices for a solution.
  1. Offload all Ethereum transaction fees (user withdrawals) to interested users as they wish to withdraw tokens for external use or sale.
  2. Cover Ethereum transaction fees by aggregating them on a timed schedule. Users would request withdrawal (from Reddit or individual subreddits), and they would be transacted on the Ethereum network every hour (or some other schedule).
  3. In a combination of the above, customers could cover aggregated fees.
  4. Integrate with alternate Ethereum roll up solutions or other proposals to aggregate minting and distribution transactions onto Ethereum.

Bonus Points

Users should be able to view their balances & transactions via a blockchain explorer-style interface
From interfaces for users who have no knowledge of blockchain technology to users who are well versed in blockchain terms such as those present in a typical block explorer, a system powered by Dragonchain has flexibility on how to provide balances and transaction data to users. Transactions can be made viewable in an Eternal Proof Report, which displays raw data along with TIME staking information and traceability all the way to Bitcoin, Ethereum, and every other Interchained network. The report shows fields such as transaction ID, timestamp, block ID, multiple verifications, and Interchain proof. See example here.
Node payouts within the Dragonchain console are listed in chronological order and can be further seen in either Dragons or USD. See example here.
In our social media platform, Dragon Den, users can see, in real-time, their NRG and MTR balances. See example here.
A new influencer app powered by Dragonchain, Raiinmaker, breaks down data into a user friendly interface that shows coin portfolio, redeemed rewards, and social scores per campaign. See example here.

Exiting is fast & simple
Withdrawing funds on Dragonchain’s console requires three clicks, however, withdrawal scenarios with more enhanced security features per Reddit’s discretion are obtainable.

Interoperability Compatibility with third party apps (wallets/contracts/etc) is necessary.
Proven interoperability at scale that surpasses the required specifications. Our entire platform consists of interoperable blockchains connected to each other and traditional systems. APIs are well documented. Third party permissions are possible with a simple smart contract without the end user being aware. No need to learn any specialized proprietary language. Any code base (not subsets) is usable within a Docker container. Interoperable with any blockchain or traditional APIs. We’ve witnessed relatively complex systems built by engineers with no blockchain or cryptocurrency experience. We’ve also demonstrated the creation of smart contracts within minutes built with BASH shell and Node.js. Please see our source code and API documentation.

Scaling solutions should be extensible and allow third parties to build on top of it Open source and extensible
APIs should be well documented and stable

Documentation should be clear and complete
For full documentation, explore our docs, SDK’s, Github repo’s, architecture documents, original Disney documentation, and other links or resources provided in this proposal.

Third-party permissionless integrations should be possible & straightforward Smart contracts are Docker based, can be written in any language, use full language (not subsets), and can therefore be integrated with any system including traditional system APIs. Simple is better. Learning an uncommon or proprietary language should not be necessary.
Advanced knowledge of mathematics, cryptography, or L2 scaling should not be required. Compatibility with common utilities & toolchains is expected.
Dragonchain business nodes and smart contracts leverage Docker to allow the use of literally any language or executable code. No proprietary language is necessary. We’ve witnessed relatively complex systems built by engineers with no blockchain or cryptocurrency experience. We’ve also demonstrated the creation of smart contracts within minutes built with BASH shell and Node.js.

Bonus

Bonus Points: Show us how it works. Do you have an idea for a cool new use case for Community Points? Build it!

TIME

Community points could be awarded to Reddit users based upon TIME too, whereas the longer someone is part of a subreddit, the more community points someone naturally gained, even if not actively commenting or sharing new posts. A daily login could be required for these community points to be credited. This grants awards to readers too and incentivizes readers to create an account on Reddit if they browse the website often. This concept could also be leveraged to provide some level of reputation based upon duration and consistency of contribution to a community subreddit.

Dragon Den

Dragonchain has already built a social media platform that harnesses community involvement. Dragon Den is a decentralized community built on the Dragonchain blockchain platform. Dragon Den is Dragonchain’s answer to fake news, trolling, and censorship. It incentivizes the creation and evaluation of quality content within communities. It could be described as being a shareholder of a subreddit or Reddit in its entirety. The more your subreddit is thriving, the more rewarding it will be. Den is currently in a public beta and in active development, though the real token economy is not live yet. There are different tokens for various purposes. Two tokens are Lair Ownership Rights (LOR) and Lair Ownership Tokens (LOT). LOT is a non-fungible token for ownership of a specific Lair. LOT will only be created and converted from LOR.
Energy (NRG) and Matter (MTR) work jointly. Your MTR determines how much NRG you receive in a 24-hour period. Providing quality content, or evaluating content will earn MTR.

Security. Users have full ownership & control of their points.
All community points awarded based upon any type of activity or gift, are secured and provable to all Interchain networks (currently BTC, ETH, ETC). Users are free to spend and withdraw their points as they please, depending on the features Reddit wants to bring into production.

Balances and transactions cannot be forged, manipulated, or blocked by Reddit or anyone else
Users can withdraw their balance to their ERC20 wallet, directly through Reddit. Reddit can cover the fees on their behalf, or the user covers this with a portion of their balance.

Users should own their points and be able to get on-chain ERC20 tokens without permission from anyone else
Through our console users can withdraw their ERC20 rewards. This can be achieved on Reddit too. Here is a walkthrough of our console, though this does not show the quick withdrawal functionality, a user can withdraw at any time. https://www.youtube.com/watch?v=aNlTMxnfVHw

Points should be recoverable to on-chain ERC20 tokens even if all third-parties involved go offline
If necessary, signed transactions from the Reddit system (e.g. Reddit + Subreddit) can be sent to the Ethereum smart contract for minting.

A public, third-party review attesting to the soundness of the design should be available
To our knowledge, at least two large corporations, including a top 3 accounting firm, have conducted positive reviews. These reviews have never been made public, as Dragonchain did not pay or contract for these studies to be released.

Bonus points
Public, third-party implementation review available or in progress
See above

Compatibility with HSMs & hardware wallets
For the purpose of this proposal, all tokenization would be on the Ethereum network using standard token contracts and as such, would be able to leverage all hardware wallet and Ethereum ecosystem services.

Other Considerations

Minting/distributing tokens is not performed by Reddit directly
This operation can be automated by smart contract on Ethereum. Subreddits can if desired have a role to play.

One off point burning, as well as recurring, non-interactive point burning (for subreddit memberships) should be possible and scalable
This is possible and scalable with interaction between Dragonchain Reddit system and Ethereum token contract(s).

Fully open-source solutions are strongly preferred
Dragonchain is fully open source (see section on Disney release after conclusion).

Conclusion

Whether it is today, or in the future, we would like to work together to bring secure flexibility to the highest standards. It is our hope to be considered by Ethereum, Reddit, and other integrative solutions so we may further discuss the possibilities of implementation. In our public demonstration, 256 million transactions were handled in our operational network on chain in 24 hours, for the low cost of $25K, which if run today would cost $625. Dragonchain’s interoperable foundation provides the atmosphere necessary to implement a frictionless community points system. Thank you for your consideration of our proposal. We look forward to working with the community to make something great!

Disney Releases Blockchain Platform as Open Source

The team at Disney created the Disney Private Blockchain Platform. The system was a hybrid interoperable blockchain platform for ledgering and smart contract development geared toward solving problems with blockchain adoption and usability. All objective evaluation would consider the team’s output a success. We released a list of use cases that we explored in some capacity at Disney, and our input on blockchain standardization as part of our participation in the W3C Blockchain Community Group.
https://lists.w3.org/Archives/Public/public-blockchain/2016May/0052.html

Open Source

In 2016, Roets proposed to release the platform as open source to spread the technology outside of Disney, as others within the W3C group were interested in the solutions that had been created inside of Disney.
Following a long process, step by step, the team met requirements for release. Among the requirements, the team had to:
  • Obtain VP support and approval for the release
  • Verify ownership of the software to be released
  • Verify that no proprietary content would be released
  • Convince the organization that there was a value to the open source community
  • Convince the organization that there was a value to Disney
  • Offer the plan for ongoing maintenance of the project outside of Disney
  • Itemize competing projects
  • Verify no conflict of interest
  • Preferred license
  • Change the project name to not use the name Disney, any Disney character, or any other associated IP - proposed Dragonchain - approved
  • Obtain legal approval
  • Approval from corporate, parks, and other business units
  • Approval from multiple Disney patent groups Copyright holder defined by Disney (Disney Connected and Advanced Technologies)
  • Trademark searches conducted for the selected name Dragonchain
  • Obtain IT security approval
  • Manual review of OSS components conducted
  • OWASP Dependency and Vulnerability Check Conducted
  • Obtain technical (software) approval
  • Offer management, process, and financial plans for the maintenance of the project.
  • Meet list of items to be addressed before release
  • Remove all Disney project references and scripts
  • Create a public distribution list for email communications
  • Remove Roets’ direct and internal contact information
  • Create public Slack channel and move from Disney slack channels
  • Create proper labels for issue tracking
  • Rename internal private Github repository
  • Add informative description to Github page
  • Expand README.md with more specific information
  • Add information beyond current “Blockchains are Magic”
  • Add getting started sections and info on cloning/forking the project
  • Add installation details
  • Add uninstall process
  • Add unit, functional, and integration test information
  • Detail how to contribute and get involved
  • Describe the git workflow that the project will use
  • Move to public, non-Disney git repository (Github or Bitbucket)
  • Obtain Disney Open Source Committee approval for release
On top of meeting the above criteria, as part of the process, the maintainer of the project had to receive the codebase on their own personal email and create accounts for maintenance (e.g. Github) with non-Disney accounts. Given the fact that the project spanned multiple business units, Roets was individually responsible for its ongoing maintenance. Because of this, he proposed in the open source application to create a non-profit organization to hold the IP and maintain the project. This was approved by Disney.
The Disney Open Source Committee approved the application known as OSSRELEASE-10, and the code was released on October 2, 2016. Disney decided to not issue a press release.
Original OSSRELASE-10 document

Dragonchain Foundation

The Dragonchain Foundation was created on January 17, 2017. https://den.social/l/Dragonchain/24130078352e485d96d2125082151cf0/dragonchain-and-disney/
submitted by j0j0r0 to ethereum [link] [comments]

How can I trust Utopia when it's not open-source?

By Due diligence, We already know of services and features which are open source and still they were found in malpractices and it took months if not years before anyone could find something out. I will give an example of something which happened recently , Brave browser was using "Referral" links whenever someone tried to open certain cryptocurrency websites the the browser replaced the link with their own referral link ...
So yes this was an open source, they got busted they apologized and the world moved on. Then we have many examples of services which we use and those are closed source, the browsers we use the OS we use or the social media platforms we spend our time on. Someone may counter the argument by saying that atleast we know who they are and they are reputable companies.
Many questions were asked by the team including why its Closed Source and Anonymous team on this detailed blog post *Skip to the part "Trust Utopia or NOT"*
Those reputable companies have made it evidently clear that they will sell your information and earn from it. That is their business model : Selling your Information.
Do check out this Intro On Utopia Website (https://u.is/en/#intro_slide)
Lets come over to Utopia now. One thing is certain that Utopia team is spending to get the word of Utopia out to the masses, Utopia could have easily organized an ICO for Crypton and launch Client once the ICO terminated and the world would have gone crazy that a Coin which is already giving what it promised BUT Utopia did not go on that route, Utopia is not about controlling or gaining anything from this.
If Utopia team is not into monetary benefits, What reasons is there not to trust Utopia ?
"If it's not money It's the data" - well run Utopia in sand-boxed environment and monitor data traffic and analyze what is being sent and received - most importantly see if there are any persistent IP addresses which keep connecting to your nodes, you won't find that in a new Utopia account. Because its decentralized and peer based system. Since the start of Utopia, many users ran various malware and packet inspection scans to answer the same queries.
The reason of an anonymous team with a closed source platform is well justified. Satoshi made a breakthrough with cryptocurrency and he kept himself anonymous, Why? Because of the same reason Utopia team is - Influence and Pressure. No one can influence the team when no one knows who is the team. I am Satoshi must have wondered many a times if keeping Bitcoin open source was the smartest of ideas as we have seen the division of effort in the shape of 'forks' that effort could was better spent in the unification of the cause and letting crypto what it was meant for.
In the end it is up to you to trust Utopia or not.
p.s. a 3rd party Code audit is still in the works
submitted by Hackology_co to Utopia1984 [link] [comments]

My top 5 (and more) arguments against the mining tax as implemented in ABC 0.21.0

These are mine, but I'd like to hear yours in the comments!
  1. Corrupting influence. Mixing monetary policy (money supply regulation, in Bitcoin: coin creation) and fiscal policy (roughly: government spending and taxing) is what central banks already do, and we know the results. Bitcoin was not designed to deliver such a mix - the newly created coin was, up to now, fully owned by the miner creating the block, and matures after a certain time when it can be spent. Miners can voluntary spend their coinbase outputs to other parties already. In this way fiscal decisions are decentralized as much possible - meaning every miner / pool gets to decide how to spend 100% of their mining block reward (or share thereof). Do you already see how Bitcoin's design removes all possible financial intermediaries - including any trusted "government" or "fund" that decides how to spend other peoples' money? If so, you already get my first point. Peter Rizun has mentioned the legal concerns around directing colluding miner funds to certain entities with expectation of results. IANAL, but I think the argument that instituting such a change on protocol level could bring BCH into conflict with security law (Howey Test) should be seriously examined.
  2. Due to how information is distributed, a centrally planned economy cannot match the efficiency of the open market. A free market is all that is needed to fund things. Miners and anyone else can already fund any kind of development (or other activities) through the existing protocol. Furthermore, we know there are successful methods of funding public goods in voluntary ways through Assurance Contracts. These have not been deployed on Bitcoin Cash before (early crowdfunding systems didn't implement them properly), but are basically ready to go now (Flipstarter) and could offer BCH an improvement even over other successful systems like Monero's Community Crowdfunding System (CCS) due to the fact that we can do this non-custodially via Bitcoin Cash scripts. Going for a miner tax based "dev fund" with nebulous administration and all the accompanying hazards seems a poor choice before we tried the voluntary route which preserves the original economic freedom and incentives of Bitcoin Cash.
  3. Increased centralization of mining and development. Going with the plan would work counter to a decentralized protocol client environment, and centralize even more power with the dominant client (ABC). The donation address whitelist is hardcoded into the client. Miners/pools who don't obey the new rules of contributing 5% of block reward to active whitelisted addresses have their blocks orphaned, lowering the chain hashrate (security) and driving away small miners who might not be able to afford the margin. This centralizes mining on BCH beyond what's necessary. Again, a free market will deliver better security and service!
  4. Sold with a veneer of false pretenses. We are told that other (non-BCH) SHA256 miners will effectively pay the cost, but this argument has been effectively debunked. The cost is paid for all BCH holders, as it comes out of the agreed upon money supply inflation. It comes at the cost of lowered BCH chain hashrate = security, with the concomitant increased risk of other miners executing attacks on BCH. Yet, holders don't get to vote right now, except by selling their BCH or converting it into hashpower. Did you know financial markets can offer instruments to let holders express their opinion about possible futures (whether they'd prefer one outcome or another) with slight or no punishment in the case of no split - i.e. actually could facilitate a no-split outcome that many BCH users & holders recognize as preferable? Another pretense is that the plan, if successful, would terminate after a limited time. This is not what regularly happens in taxpayer-funded government programs, and it is paradoxical to assume that a measure to support ongoing maintenance and development would, if deemed successful in a trial run, be expected to be terminated. Especially if the people receiving the funds are literally the ones deciding and writing the rules. In governments we at least came up with separation of powers (legislative, judicial, executive). Why should be mix up powers again? Absolute power corrupts absolutely. Serious developers also recognize that the dollar amounts we are talking about in the proposed plan are too low to expect completion within the previously announced limited timeframes. Giving a good hint that the limited timeframe was a nothing but a public pacifier when planners already expect it to continue.
  5. The proposal is poorly conceived in terms of safety against malicious activation. Only 66% of hashrate need to vote for it over a two week period. Previously, BCH miners objected to any form of hashrate voting on BCH with the argument that it is still a very-low hashrate minority fork. That has not changed materially, but suddenly we are supposed to accept that hashrate voting on our minority coin is safe. Can't have it both ways. As an additional point, there is no 6 month sunset clause built into the implementation, and it seems removed from the plan agreed between ABC and miners (as per recent ABC website post). This completely reneges on the "update" previously presented to the community in that regard, re-affirming that there is no serious commitment to ending this after a limited time.
I probably squeezed in too many explanations.
Originally my aim was to get a short summary. I should try to sum it up better, but I know there are many people who could do a much better job at that. Please speak up, correct me where you feel I'm wrong, and add points that you think are missing!
P.S. I fully realize that the ones pushing this plan are not likely to be swayed by any of these arguments.
I am presenting mine here in hopes to encourage further discussion, and I hope you will do the same, so everyone is armed with knowledge, going into what looks like it could be an escalating dispute within our community.
Perhaps though, there is a minute chance that backers of the plan could see the danger in the split that they are creating. I still have hope, but I'm also prepared to act.
submitted by ftrader to btc [link] [comments]

Filecoin | Development Status and Mining Progress

Author: Gamals Ahmed, CoinEx Business Ambassador
https://preview.redd.it/5bqakdqgl3g51.jpg?width=865&format=pjpg&auto=webp&s=b709794863977eb6554e3919b9e00ca750e3e704
A decentralized storage network that transforms cloud storage into an account market. Miners obtain the integrity of the original protocol by providing data storage and / or retrieval. On the contrary, customers pay miners to store or distribute data and retrieve it.
Filecoin announced, that there will be more delays before its main network is officially launched.
Filecoin developers postponed the release date of their main network to late July to late August 2020.
As mentioned in a recent announcement, the Filecoin team said that the initiative completed the first round of the internal protocol security audit. Platform developers claim that the results of the review showed that they need to make several changes to the protocol’s code base before performing the second stage of the software testing process.
Created by Protocol Labs, Filecoin was developed using File System (IPFS), which is a peer-to-peer data storage network. Filecoin will allow users to trade storage space in an open and decentralized market.
Filecoin developers implemented one of the largest cryptocurrency sales in 2017. They have privately obtained over $ 200 million from professional or accredited investors, including many institutional investors.
The main network was slated to launch last month, but in February 2020, the Philly Queen development team delayed the release of the main network between July 15 and July 17, 2020.
They claimed that the outbreak of the Coronavirus (COVID-19) in China was the main cause of the delay. The developers now say that they need more time to solve the problems found during a recent codecase audit.
The Filecoin team noted the following:
“We have drafted a number of protocol changes to ensure that building our major network launch is safe and economically sound.” The project developers will add them to two different implementations of Filecoin (Lotus and go-filecoin) in the coming weeks.
Filecoin developers conducted a survey to allow platform community members to cast their votes on three different launch dates for Testnet Phase 2 and mainnet.
The team reported that the community gave their votes. Based on the vote results, the Filecoin team announced a “conservative” estimate that the second phase of the network test should begin by May 11, 2020. The main Filecoin network may be launched sometime between July 20 and August 21, 2020.
The updates to the project can be found on the Filecoin Road Map.
Filecoin developers stated:
“This option will make us get the most important protocol changes first, and then implement the rest as protocol updates during testnet.” Filecoin is back down from the final test stage.
Another filecoin decentralized storage network provider launched its catalytic test network, the final stage of the storage network test that supports the blockchain.
In a blog post on her website, Filecoin said she will postpone the last test round until August. The company also announced a calibration period from July 20 to August 3 to allow miners to test their mining settings and get an idea of how competition conditions affected their rewards.
Filecoin had announced earlier last month that the catalytic testnet test would precede its flagship launch. The delay in the final test also means that the company has returned the main launch window between August 31 and September 21.
Despite the lack of clear incentives for miners and multiple delays, Filecoin has succeeded in attracting huge interest, especially in China. Investors remained highly speculating on the network’s mining hardware and its premium price.
Mining in Filecoin
In most blockchain protocols, “miners” are network participants who do the work necessary to promote and maintain the blockchain. To provide these services, miners are compensated in the original cryptocurrency.
Mining in Filecoin works completely differently — instead of contributing to computational power, miners contribute storage capacity to use for dealing with customers looking to store data.
Filecoin will contain several types of miners:
Storage miners responsible for storing files and data on the network. Miners retrieval, responsible for providing quick tubes for file recovery. Miners repair to be carried out.
Storage miners are the heart of the network. They earn Filecoin by storing data for clients, and computerizing cipher directories to check storage over time. The probability of earning the reward reward and transaction fees is proportional to the amount of storage that the Miner contributes to the Filecoin network, not the hash power.
Retriever miners are the veins of the network. They earn Filecoin by winning bids and mining fees for a specific file, which is determined by the market value of the said file size. Miners bandwidth and recovery / initial transaction response time will determine its ability to close recovery deals on the network.
The maximum bandwidth of the recovery miners will determine the total amount of deals that it can enter into.
In the current implementation, the focus is mostly on storage miners, who sell storage capacity for FIL.

Hardware recommendations

The current system specifications recommended for running the miner are:
Compared to the hardware requirements for running a validity checker, these standards are much higher — although they definitely deserve it. Since these will not increase in the presumed future, the money spent on Filecoin mining hardware will provide users with many years of reliable service, and they pay themselves many times. Think of investing as a small business for cloud storage. To launch a model on the current data hosting model, it will cost millions of dollars in infrastructure and logistics to get started. With Filecoin, you can do the same for a few thousand dollars.
Proceed to mining
Deals are the primary function of the Filecoin network, and it represents an agreement between a client and miners for a “storage” contract.
Once the customer decides to have a miner to store based on the available capacity, duration and price required, he secures sufficient funds in a linked portfolio to cover the total cost of the deal. The deal is then published once the mine accepts the storage agreement. By default, all Filecoin miners are set to automatically accept any deal that meets their criteria, although this can be disabled for miners who prefer to organize their deals manually.
After the deal is published, the customer prepares the data for storage and then transfers it to the miner. Upon receiving all the data, the miner fills in the data in a sector, closes it, and begins to provide proofs to the chain. Once the first confirmation is obtained, the customer can make sure the data is stored correctly, and the deal has officially started.
Throughout the deal, the miner provides continuous proofs to the chain. Clients gradually pay with money they previously closed. If there is missing or late evidence, the miner is punished. More information about this can be found in the Runtime, Cut and Penalties section of this page.
At Filecoin, miners earn two different types of rewards for their efforts: storage fees and reward prevention.
Storage fees are the fees that customers pay regularly after reaching a deal, in exchange for storing data. This fee is automatically deposited into the withdrawal portfolio associated with miners while they continue to perform their duties over time, and is locked for a short period upon receipt.
Block rewards are large sums given to miners calculated on a new block. Unlike storage fees, these rewards do not come from a linked customer; Instead, the new FIL “prints” the network as an inflationary and incentive measure for miners to develop the chain. All active miners on the network have a chance to get a block bonus, their chance to be directly proportional to the amount of storage space that is currently being contributed to the network.
Duration of operation, cutting and penalties
“Slashing” is a feature found in most blockchain protocols, and is used to punish miners who fail to provide reliable uptime or act maliciously against the network.
In Filecoin, miners are susceptible to two different types of cut: storage error cut, unanimously reduce error.
Storage Error Reduction is a term used to include a wider range of penalties, including error fees, sector penalties, and termination fees. Miners must pay these penalties if they fail to provide reliability of the sector or decide to leave the network voluntarily.
An error fee is a penalty that a miner incurs for each non-working day. Sector punishment: A penalty incurred by a miner of a disrupted sector for which no error was reported before the WindowPoSt inspection.
The sector will pay an error fee after the penalty of the sector once the error is discovered.
Termination Fee: A penalty that a miner incurs when a sector is voluntary or involuntarily terminated and removed from the network.
Cutting consensus error is the penalty that a miner incurs for committing consensus errors. This punishment applies to miners who have acted maliciously against the network consensus function.
Filecoin miners
Eight of the top 10 Felticoin miners are Chinese investors or companies, according to the blockchain explorer, while more companies are selling cloud mining contracts and distributed file sharing system hardware. CoinDesk’s Wolfe Chao wrote: “China’s craze for Filecoin may have been largely related to the long-standing popularity of crypto mining in the country overall, which is home to about 65% of the computing power on Bitcoin at discretion.”
With Filecoin approaching the launch of the mainnet blocknet — after several delays since the $ 200 million increase in 2017 — Chinese investors are once again speculating strongly about network mining devices and their premium prices.
Since Protocol Labs, the company behind Filecoin, released its “Test Incentives” program on June 9 that was scheduled to start in a week’s time, more than a dozen Chinese companies have started selling cloud mining contracts and hardware — despite important details such as economics Mining incentives on the main network are still endless.
Sales volumes to date for each of these companies can range from half a million to tens of millions of dollars, according to self-reported data on these platforms that CoinDesk has watched and interviews with several mining hardware manufacturers.
Filecoin’s goal is to build a distributed storage network with token rewards to spur storage hosting as a way to drive wider adoption. Protocol Labs launched a test network in December 2019. But the tokens mined in the testing environment so far are not representative of the true silicon coin that can be traded when the main network is turned on. Moreover, the mining incentive economics on testnet do not represent how final block rewards will be available on the main network.
However, data from Blockecoin’s blocknetin testnet explorers show that eight out of 10 miners with the most effective mining force on testnet are currently Chinese miners.
These eight miners have about 15 petabytes (PB) of effective storage mining power, accounting for more than 85% of the total test of 17.9 petable. For the context, 1 petabyte of hard disk storage = 1000 terabytes (terabytes) = 1 million gigabytes (GB).
Filecoin craze in China may be closely related to the long-standing popularity of crypt mining in the country overall, which is home to about 65% of the computing power on Bitcoin by estimation. In addition, there has been a lot of hype in China about foreign exchange mining since 2018, as companies promote all types of devices when the network is still in development.
“Encryption mining has always been popular in China,” said Andy Tien, co-founder of 1475, one of several mining hardware manufacturers in Philquin supported by prominent Chinese video indicators such as Fenbushi and Hashkey Capital.
“Even though the Velikoyen mining process is more technologically sophisticated, the idea of mining using hard drives instead of specialized machines like Bitcoin ASIC may be a lot easier for retailers to understand,” he said.
Meanwhile, according to Feixiaohao, a Chinese service comparable to CoinMarketCap, nearly 50 Chinese crypto exchanges are often somewhat unknown with some of the more well-known exchanges including Gate.io and Biki — have listed trading pairs for Filecoin currency contracts for USDT.
In bitcoin mining, at the current difficulty level, one segment per second (TH / s) fragmentation rate is expected to generate around 0.000008 BTC within 24 hours. The higher the number of TH / s, the greater the number of bitcoins it should be able to produce proportionately. But in Filecoin, the efficient mining force of miners depends on the amount of data stamped on the hard drive, not the total size of the hard drive.
To close data in the hard drive, the Filecoin miner still needs processing power, i.e. CPU or GPU as well as RAM. More powerful processors with improved software can confine data to the hard drive more quickly, so miners can combine more efficient mining energy faster on a given day.
As of this stage, there appears to be no transparent way at the network level for retail investors to see how much of the purchased hard disk drive was purchased which actually represents an effective mining force.
The U.S.-based Labs Protocol was behind Filecoin’s initial coin offer for 2017, which raised an astonishing $ 200 million.
This was in addition to a $ 50 million increase in private investment supported by notable venture capital projects including Sequoia, Anderson Horowitz and Union Square Ventures. CoinDk’s parent company, CoinDk, has also invested in Protocol Labs.
After rounds of delay, Protocol Protocols said in September 2019 that a testnet launch would be available around December 2019 and the main network would be rolled out in the first quarter of 2020.
The test started as promised, but the main network has been delayed again and is now expected to launch in August 2020. What is Filecoin mining process?
Filecoin mainly consists of three parts: the storage market (the chain), the blockecin Filecoin, and the search market (under the chain). Storage and research market in series and series respectively for security and efficiency. For users, the storage frequency is relatively low, and the security requirements are relatively high, so the storage process is placed on the chain. The retrieval frequency is much higher than the storage frequency when there is a certain amount of data. Given the performance problem in processing data on the chain, the retrieval process under the chain is performed. In order to solve the security issue of payment in the retrieval process, Filecoin adopts the micro-payment strategy. In simple terms, the process is to split the document into several copies, and every time the user gets a portion of the data, the corresponding fee is paid. Types of mines corresponding to Filecoin’s two major markets are miners and warehousers, among whom miners are primarily responsible for storing data and block packages, while miners are primarily responsible for data query. After the stable operation of the major Filecoin network in the future, the mining operator will be introduced, who is the main responsible for data maintenance.
In the initial release of Filecoin, the request matching mechanism was not implemented in the storage market and retrieval market, but the takeover mechanism was adopted. The three main parts of Filecoin correspond to three processes, namely the stored procedure, retrieval process, packaging and reward process. The following figure shows the simplified process and the income of the miners:
The Filecoin mining process is much more complicated, and the important factor in determining the previous mining profit is efficient storage. Effective storage is a key feature that distinguishes Filecoin from other decentralized storage projects. In Filecoin’s EC consensus, effective storage is similar to interest in PoS, which determines the likelihood that a miner will get the right to fill, that is, the proportion of miners effectively stored in the entire network is proportional to final mining revenue.
It is also possible to obtain higher effective storage under the same hardware conditions by improving the mining algorithm. However, the current increase in the number of benefits that can be achieved by improving the algorithm is still unknown.
It seeks to promote mining using Filecoin Discover
Filecoin announced Filecoin Discover — a step to encourage miners to join the Filecoin network. According to the company, Filecoin Discover is “an ever-growing catalog of numerous petabytes of public data covering literature, science, art, and history.” Miners interested in sharing can choose which data sets they want to store, and receive that data on a drive at a cost. In exchange for storing this verified data, miners will earn additional Filecoin above the regular block rewards for storing data. Includes the current catalog of open source data sets; ENCODE, 1000 Genomes, Project Gutenberg, Berkley Self-driving data, more projects, and datasets are added every day.
Ian Darrow, Head of Operations at Filecoin, commented on the announcement:
“Over 2.5 quintillion bytes of data are created every day. This data includes 294 billion emails, 500 million tweets and 64 billion messages on social media. But it is also climatology reports, disease tracking maps, connected vehicle coordinates and much more. It is extremely important that we maintain data that will serve as the backbone for future research and discovery”.
Miners who choose to participate in Filecoin Discover may receive hard drives pre-loaded with verified data, as well as setup and maintenance instructions, depending on the company. The Filecoin team will also host the Slack (fil-Discover-support) channel where miners can learn more.
Filecoin got its fair share of obstacles along the way. Last month Filecoin announced a further delay before its main network was officially launched — after years of raising funds.
In late July QEBR (OTC: QEBR) announced that it had ceded ownership of two subsidiaries in order to focus all of the company’s resources on building blockchain-based mining operations.
The QEBR technology team previously announced that it has proven its system as a Filecoin node valid with CPU, GPU, bandwidth and storage compatibility that meets all IPFS guidelines. The QEBR test system is connected to the main Filecoin blockchain and the already mined filecoin coin has already been tested.
“The disclosure of Sheen Boom and Jihye will allow our team to focus only on the upcoming global launch of Filecoin. QEBR branch, Shenzhen DZD Digital Technology Ltd. (“ DZD “), has a strong background in blockchain development, extraction Data, data acquisition, data processing, data technology research. We strongly believe Filecoin has the potential to be a leading blockchain-based cryptocurrency and will make every effort to make QEBR an important player when Mainecoin mainnet will be launched soon”.
IPFS and Filecoin
Filecoin and IPFS are complementary protocols for storing and sharing data in a decentralized network. While users are not required to use Filecoin and IPFS together, the two combined are working to resolve major failures in the current web infrastructure.
IPFS
It is an open source protocol that allows users to store and transmit verifiable data with each other. IPFS users insist on data on the network by installing it on their own device, to a third-party cloud service (known as Pinning Services), or through community-oriented systems where a group of individual IPFS users share resources to ensure the content stays live.
The lack of an integrated catalytic mechanism is the challenge Filecoin hopes to solve by allowing users to catalyze long-term distributed storage at competitive prices through the storage contract market, while maintaining the efficiency and flexibility that the IPFS network provides.
Using IPFS
In IPFS, the data is hosted by the required data installation nodes. For data to persist while the user node is offline, users must either rely on their other peers to install their data voluntarily or use a central install service to store data.
Peer-to-peer reliance caching data may be a good thing as one or multiple organizations share common files on an internal network, or where strong social contracts can be used to ensure continued hosting and preservation of content in the long run. Most users in an IPFS network use an installation service.
Using Filecoin
The last option is to install your data in a decentralized storage market, such as Filecoin. In Filecoin’s structure, customers make regular small payments to store data when a certain availability, while miners earn those payments by constantly checking the integrity of this data, storing it, and ensuring its quick recovery. This allows users to motivate Filecoin miners to ensure that their content will be live when it is needed, a distinct advantage of relying only on other network users as required using IPFS alone.
Filecoin, powered by IPFS
It is important to know that Filecoin is built on top of IPFS. Filecoin aims to be a very integrated and seamless storage market that takes advantage of the basic functions provided by IPFS, they are connected to each other, but can be implemented completely independently of each other. Users do not need to interact with Filecoin in order to use IPFS.
Some advantages of sharing Filecoin with IPFS:
Of all the decentralized storage projects, Filecoin is undoubtedly the most interested, and IPFS has been running stably for two years, fully demonstrating the strength of its core protocol.
Filecoin’s ability to obtain market share from traditional central storage depends on end-user experience and storage price. Currently, most Filecoin nodes are posted in the IDC room. Actual deployment and operation costs are not reduced compared to traditional central cloud storage, and the storage process is more complicated.
PoRep and PoSt, which has a large number of proofs of unknown operation, are required to cause the actual storage cost to be so, in the early days of the release of Filecoin. The actual cost of storing data may be higher than the cost of central cloud storage, but the initial storage node may reduce the storage price in order to obtain block rewards, which may result in the actual storage price lower than traditional central cloud storage.
In the long term, Filecoin still needs to take full advantage of its P2P storage, convert storage devices from specialization to civil use, and improve its algorithms to reduce storage costs without affecting user experience. The storage problem is an important problem to be solved in the blockchain field, so a large number of storage projects were presented at the 19th Web3 Summit. IPFS is an important part of Web3 visibility. Its development will affect the development of Web3 to some extent. Likewise, Web3 development somewhat determines the future of IPFS. Filecoin is an IPFS-based storage class project initiated by IPFS. There is no doubt that he is highly expected.
Resources :
  1. https://www.coindesk.com/filecoin-pushes-back-final-testing-phase-announces-calibration-period-for-miners
  2. https://docs.filecoin.io/mine/#types-of-miners https://www.nasdaq.com/articles/inside-the-craze-for-filecoin-crypto-mining-in-china-2020-07-12؟amp
  3. https://www.prnewswire.com/news-releases/qebr-streamlines-holdings-to-concentrate-on-filecoin-development-and-mining-301098731.html
  4. https://www.crowdfundinsider.com/2020/05/161200-filecoin-seeks-to-boost-mining-with-filecoin-discove
  5. https://zephyrnet.com/filecoin-seeks-to-boost-mining-with-filecoin-discove
  6. https://docs.filecoin.io/introduction/ipfs-and-filecoin/#filecoin-powered-by-ipfs
submitted by CoinEx_Institution to filecoin [link] [comments]

Electrum wont connect to mynode

having some issues with Electrum wallet on Ubuntu 20.04 LTS. i got it to install properly with no issues. but it seems like i am now have trouble connecting it to my node, below is what my .desktop file looks like
# If you want Electrum to appear in a Linux app launcher ("start menu"), install this by doing:
# sudo desktop-file-install electrum.desktop

[Desktop Entry]
Comment=Lightweight Bitcoin Client
Exec=sh -c "PATH=\"\\$HOME/.local/bin:\\$PATH\"; electrum --oneserver --server localhost:50001:t %u"
GenericName[en_US]=Bitcoin Wallet
GenericName=Bitcoin Wallet
Icon=electrum
Name[en_US]=Electrum Bitcoin Wallet
Name=Electrum Bitcoin Wallet
Categories=Finance;Network;
StartupNotify=true
StartupWMClass=electrum
Terminal=false
Type=Application
MimeType=x-scheme-handlebitcoin;
Actions=Testnet;

[Desktop Action Testnet]
Exec=sh -c "PATH=\"\\$HOME/.local/bin:\\$PATH\"; electrum --testnet %u"
Name=Testnet mode


when opening up the wallet, i get the red dot on the bottom right hand corner, i can ping and access mynode via the local 192. address and i see electrum server is running. does it matter where the electrum.desktop file is located? as of right now i have it under /home/gp11/Downloads. is there anything else i can check? even if i remove electrum --oneserver --server localhost:50001:t i still get the same result with no connection, where i am thinking if i remove the line of code it should connect to other nodes.
currently using myNode community Version 0.2.09 any help here would be appreciated - thanks in advance.
submitted by lifeofgp to Electrum [link] [comments]

Review and Prospect of Crypto Economy-Development and Evolution of Consensus Mechanism (2)

Review and Prospect of Crypto Economy-Development and Evolution of Consensus Mechanism (2)

https://preview.redd.it/a51zsja94db51.png?width=567&format=png&auto=webp&s=99e8080c9e9b1fb5e11cbd70f915f9cb37188f81
Foreword
The consensus mechanism is one of the important elements of the blockchain and the core rule of the normal operation of the distributed ledger. It is mainly used to solve the trust problem between people and determine who is responsible for generating new blocks and maintaining the effective unification of the system in the blockchain system. Thus, it has become an everlasting research hot topic in blockchain.
This article starts with the concept and role of the consensus mechanism. First, it enables the reader to have a preliminary understanding of the consensus mechanism as a whole; then starting with the two armies and the Byzantine general problem, the evolution of the consensus mechanism is introduced in the order of the time when the consensus mechanism is proposed; Then, it briefly introduces the current mainstream consensus mechanism from three aspects of concept, working principle and representative project, and compares the advantages and disadvantages of the mainstream consensus mechanism; finally, it gives suggestions on how to choose a consensus mechanism for blockchain projects and pointed out the possibility of the future development of the consensus mechanism.
Contents
First, concept and function of the consensus mechanism
1.1 Concept: The core rules for the normal operation of distributed ledgers
1.2 Role: Solve the trust problem and decide the generation and maintenance of new blocks
1.2.1 Used to solve the trust problem between people
1.2.2 Used to decide who is responsible for generating new blocks and maintaining effective unity in the blockchain system
1.3 Mainstream model of consensus algorithm
Second, the origin of the consensus mechanism
2.1 The two armies and the Byzantine generals
2.1.1 The two armies problem
2.1.2 The Byzantine generals problem
2.2 Development history of consensus mechanism
2.2.1 Classification of consensus mechanism
2.2.2 Development frontier of consensus mechanism
Third, Common Consensus System
Fourth, Selection of consensus mechanism and summary of current situation
4.1 How to choose a consensus mechanism that suits you
4.1.1 Determine whether the final result is important
4.1.2 Determine how fast the application process needs to be
4.1.2 Determining the degree to which the application requires for decentralization
4.1.3 Determine whether the system can be terminated
4.1.4 Select a suitable consensus algorithm after weighing the advantages and disadvantages
4.2 Future development of consensus mechanism
Last lecture review: Chapter 1 Concept and Function of Consensus Mechanism plus Chapter 2 Origin of Consensus Mechanism
Chapter 3 Common Consensus Mechanisms (Part 1)
Figure 6 Summary of relatively mainstream consensus mechanisms
📷
https://preview.redd.it/9r7q3xra4db51.png?width=567&format=png&auto=webp&s=bae5554a596feaac948fae22dffafee98c4318a7
Source: Hasib Anwar, "Consensus Algorithms: The Root Of The Blockchain Technology"
The picture above shows 14 relatively mainstream consensus mechanisms summarized by a geek Hasib Anwar, including PoW (Proof of Work), PoS (Proof of Stake), DPoS (Delegated Proof of Stake), LPoS (Lease Proof of Stake), PoET ( Proof of Elapsed Time), PBFT (Practical Byzantine Fault Tolerance), SBFT (Simple Byzantine Fault Tolerance), DBFT (Delegated Byzantine Fault Tolerance), DAG (Directed Acyclic Graph), Proof-of-Activity (Proof of Activity), Proof-of- Importance (Proof of Importance), Proof-of-Capacity (Proof of Capacity), Proof-of-Burn ( Proof of Burn), Proof-of-Weight (Proof of Weight).
Next, we will mainly introduce and analyze the top ten consensus mechanisms of the current blockchain.
》POW
-Concept:
Work proof mechanism. That is, the proof of work means that it takes a certain amount of computer time to confirm the work.
-Principle:
Figure 7 PoW work proof principle
📷
https://preview.redd.it/xupacdfc4db51.png?width=554&format=png&auto=webp&s=3b6994641f5890804d93dfed9ecfd29308c8e0cc
The PoW represented by Bitcoin uses the SHA-256 algorithm function, which is a 256-bit hash algorithm in the password hash function family:
Proof of work output = SHA256 (SHA256 (block header));
if (output of proof of work if (output of proof of work >= target value), change the random number, recursive i logic, continue to compare with the target value.
New difficulty value = old difficulty value* (time spent by last 2016 blocks /20160 minutes)
Target value = maximum target value / difficulty value
The maximum target value is a fixed number. If the last 2016 blocks took less than 20160 minutes, then this coefficient will be small, and the target value will be adjusted bigger, if not, the target value will be adjusted smaller. Bitcoin mining difficulty and block generation speed will be inversely proportional to the appropriate adjustment of block generation speed.
-Representative applications: BTC, etc.
》POS
-Concept:
Proof of stake. That is, a mechanism for reaching consensus based on the holding currency. The longer the currency is held, the greater the probability of getting a reward.
-Principle:
PoS implementation algorithm formula: hash(block_header) = Coin age calculation formula: coinage = number of coins * remaining usage time of coins
Among them, coinage means coin age, which means that the older the coin age, the easier it is to get answers. The calculation of the coin age is obtained by multiplying the coins owned by the miner by the remaining usage time of each coin, which also means that the more coins you have, the easier it is to get answers. In this way, pos solves the problem of wasting resources in pow, and miners cannot own 51% coins from the entire network, so it also solves the problem of 51% attacks.
-Representative applications: ETH, etc.
》DPoS
-Concept:
Delegated proof of stake. That is, currency holding investors select super nodes by voting to operate the entire network , similar to the people's congress system.
-Principle:
The DPOS algorithm is divided into two parts. Elect a group of block producers and schedule production.
Election: Only permanent nodes with the right to be elected can be elected, and ultimately only the top N witnesses can be elected. These N individuals must obtain more than 50% of the votes to be successfully elected. In addition, this list will be re-elected at regular intervals.
Scheduled production: Under normal circumstances, block producers take turns to generate a block every 3 seconds. Assuming that no producer misses his order, then the chain they produce is bound to be the longest chain. When a witness produces a block, a block needs to be generated every 2s. If the specified time is exceeded, the current witness will lose the right to produce and the right will be transferred to the next witness. Then the witness is not only unpaid, but also may lose his identity.
-Representative applications: EOS, etc.
》DPoW
-Concept:
Delayed proof of work. A new-generation consensus mechanism based on PoB and DPoS. Miners use their own computing power, through the hash algorithm, and finally prove their work, get the corresponding wood, wood is not tradable. After the wood has accumulated to a certain amount, you can go to the burning site to burn the wood. This can achieve a balance between computing power and mining rights.
-Principle:
In the DPoW-based blockchain, miners are no longer rewarded tokens, but "wood" that can be burned, burning wood. Miners use their own computing power, through the hash algorithm, and finally prove their work, get the corresponding wood, wood is not tradable. After the wood has accumulated to a certain amount, you can go to the burning site to burn the wood. Through a set of algorithms, people who burn more wood or BP or a group of BP can obtain the right to generate blocks in the next event segment, and get rewards (tokens) after successful block generation. Since more than one person may burn wood in a time period, the probability of producing blocks in the next time period is determined by the amount of wood burned by oneself. The more it is burned, the higher the probability of obtaining block rights in the next period.
Two node types: notary node and normal node.
The 64 notary nodes are elected by the stakeholders of the dPoW blockchain, and the notarized confirmed blocks can be added from the dPoW blockchain to the attached PoW blockchain. Once a block is added, the hash value of the block will be added to the Bitcoin transaction signed by 33 notary nodes, and a hash will be created to the dPow block record of the Bitcoin blockchain. This record has been notarized by most notary nodes in the network. In order to avoid wars on mining between notary nodes, and thereby reduce the efficiency of the network, Komodo designed a mining method that uses a polling mechanism. This method has two operating modes. In the "No Notary" (No Notary) mode, all network nodes can participate in mining, which is similar to the traditional PoW consensus mechanism. In the "Notaries Active" mode, network notaries use a significantly reduced network difficulty rate to mine. In the "Notary Public Activation" mode, each notary public is allowed to mine a block with its current difficulty, while other notary public nodes must use 10 times the difficulty of mining, and all normal nodes use 100 times the difficulty of the notary public node.
Figure 8 DPoW operation process without a notary node
📷
https://preview.redd.it/3yuzpemd4db51.png?width=500&format=png&auto=webp&s=f3bc2a1c97b13cb861414d3eb23a312b42ea6547
-Representative applications: CelesOS, Komodo, etc.
CelesOS Research Institute丨DPoW consensus mechanism-combustible mining and voting
》PBFT
-Concept:
Practical Byzantine fault tolerance algorithm. That is, the complexity of the algorithm is reduced from exponential to polynomial level, making the Byzantine fault-tolerant algorithm feasible in practical system applications.
-Principle:
Figure 9 PBFT algorithm principle
📷
https://preview.redd.it/8as7rgre4db51.png?width=567&format=png&auto=webp&s=372be730af428f991375146efedd5315926af1ca
First, the client sends a request to the master node to call the service operation, and then the master node broadcasts other copies of the request. All copies execute the request and send the result back to the client. The client needs to wait for f+1 different replica nodes to return the same result as the final result of the entire operation.
Two qualifications: 1. All nodes must be deterministic. That is to say, the results of the operation must be the same under the same conditions and parameters. 2. All nodes must start from the same status. Under these two limited qualifications, even if there are failed replica nodes, the PBFT algorithm agrees on the total order of execution of all non-failed replica nodes, thereby ensuring security.
-Representative applications: Tendermint Consensus, etc.
Next Lecture: Chapter 3 Common Consensus Mechanisms (Part 2) + Chapter 4 Consensus Mechanism Selection and Status Summary
CelesOS
As the first DPOW financial blockchain operating system, CelesOS adopts consensus mechanism 3.0 to break through the "impossible triangle", which can provide high TPS while also allowing for decentralization. Committed to creating a financial blockchain operating system that embraces supervision, providing services for financial institutions and the development of applications on the supervision chain, and formulating a role and consensus ecological supervision layer agreement for supervision.
The CelesOS team is dedicated to building a bridge between blockchain and regulatory agencies/financial industry. We believe that only blockchain technology that cooperates with regulators will have a real future. We believe in and contribute to achieving this goal.

📷Website
https://www.celesos.com/
📷 Telegram
https://t.me/celeschain
📷 Twitter
https://twitter.com/CelesChain
📷 Reddit
https://www.reddit.com/useCelesOS
📷 Medium
https://medium.com/@celesos
📷 Facebook
https://www.facebook.com/CelesOS1
📷 Youtube
https://www.youtube.com/channel/UC1Xsd8wU957D-R8RQVZPfGA
submitted by CelesOS to u/CelesOS [link] [comments]

aelf’s Blockchain-based Digital Asset Identification Standard approved by IEEE

aelf’s Blockchain-based Digital Asset Identification Standard approved by IEEE
Author: Ma Haobo

https://preview.redd.it/m1jtaghbqt651.png?width=1280&format=png&auto=webp&s=4dd933b2b9b79a9de0c6eaeaac42a66ec6868c7e
Recently, the Standard for Blockchain-based Digital Asset Identification, submitted by aelf, was approved by the IEEE SA Standards Board New Standards Committee (NesCom). The standard specifies methods and practices of crypto asset identification. The standard also addresses attributes of the blockchain system digit asset identification including but not limited to data structure, data format, and related asset management operation specifications.
The purpose of this standard is to improve digital asset management with an asset identification specification in blockchain systems. The standard aims to provide a data format and structure references for organizations designing digital asset identification solutions — providing digital asset services and setting up operational specifications for organizations.
Current Situation and Problems of Assets Management on the chain.
In the blockchain system, the unspecified participants usually work together under set contract rules to complete a social production and management activity on the blockchain. Some of these activities are closely related to assets, such as payments, loans, asset transactions, games and entertainment, etc. .
There are various ways to define assets within a blockchain as well as when compared to other blockchains. For example, in Ethereum, ETH is an asset that is directly constrained by the underlying code of the block chain, while a Fungible token is defined by the contract interface ERC20, and a Non-Fungible token is defined by ERC721. There are also emerging asset agreements such as ERC998 and ERC1155.
Most users utilize a blockchain through specific terminals, which usually includes a blockchain browser, wallet, decentralized applications (DAPP), etc. By defining standards through contract interfaces, these users’ terminals can handle various assets in a standardized way. These DApps usually need to adapt to different contract interfaces, but also deal with non-contract defined assets like ETH. When these terminals need to support different blockchains, they require extra work to adapt.
The number of interfaces that user terminals need to deal with is increasing with the emergence of more blockchain systems. But most functions are equivalent in the assets definition. At the same time, there is a growing need to move assets from one chain to another chain. For example, there are some BTC value anchored assets in Ethereum, USDT is issued on bitcoin network and Ethereum network at the same time, and the assets on the aelf main-chain and side-chain can be transferred directly. But there is not a unified standard to solve the cross-chain data communication problem in the whole blockchain industry.
What a common asset standard might do to an industry
The birth of wETH is a great place to talk about “industry change” . wETH, which is Wrapped Ether, is an ETH asset Wrapped under ERC20. As mentioned above, ETH is a non-contractual asset, but why redefine it under ERC20? Some decentralised exchanges in Ethereum, which typically deal with ERC20 assets. But ETH, as one of the key assets in Ethereum, also needed to be backed by these decentralised exchanges, so wETH was born. Users can get the same amount wETH after locking ETH in the contract. Accordingly, users will be able to get the same amount ETH by destroying the wETH in the contract, so users can exchange any ERC20 Token including the ETH in these decentralized exchanges. This seems to be a good solution. However the transformation operation on the chain may bring permanent system complexity.
Users’ needs will always be different. After solving the problems of Eth and wETH, people hope to adapt the transaction to BTC. Due to the isomeric chain, there is no good atomic transfer scheme so far. Most BTC assets anchored in Ethereum are anchored by mortgages. The risk of the centralized BTC mortgage scheme lies in the safe custody of the mortgaged BTC. Systematic risks associated with the Ethereum on-chain mortgaged asset revolves around price fluctuations. Moreover, each scheme is neither simple nor elegant. When simple requirements face complex solutions, we need a simple solution.
Challenges may also arise when conducting Defi activities on a single chain as Ethereum transaction volume increases. When the trading volume increased in March 2020, the Maker’s data source could not keep up with outside real prices, and some mortgage orders went awry. When a single chain is not big enough to handle a high number of data transactions, it may be better to process these assets on higher performance cross chains, such as EOS. But we can’t deal with the ERC20 assets on EOS. Of course, aelf can not currently deal with ERC20 assets.
Current blockchain systems, on-chain assets, and especially fungible tokens, have special commonalities. Some cryptocurrency wallets have achieved compatibility with multiple blockchain systems. A unified blockchain asset standard is not specific to a certain kind of blockchain system and can drastically reduce the systemic costs of the entire industry.

IEEE Digital Asset Standard Proposals Overview

The IEEE digital asset proposal, submitted by aelf, defines the digital asset standard in terms of data structure, data format specification and management operation specifications related to asset identification.
Combined with the digital assets demand of blockchain systems, such as public and alliance chains, a flexible asset standard with strong versatility and multiple options is necessary.
In this standard, some assets’ properties will be defined, such as name, supply, decimal places, etc. Some basic operations are also defined, such as distribution, destruction, migration, and so on.
At the same time, we will define the standard form of cross-chain transfers on the premise that cross-chain data can be synchronized normally. In this regard, the aelf team members are continuing to invest in research and development. The aelf team also launched the Cross-Chain Transfer Protocol (CCTP), and held cross-chain transfer testing and a hacker bounty between the Ethereum and aelf testnet.
Expectations and perspectives on digital asset standards
If such a standard can be implemented, users can use a client to process various digital assets without difference. For example, if a user got a rare item in the EOS blockchain game, he can also sell the item to get USDT in an NFT exchange on Ethereum, and then sell the USDT to buy the BTC on the unique side-chain of aelf’s decentralized exchange (BTC/USDT), where only transactions for the conversion of BTC to USDT are processed.
Based on existing mainstream blockchain systems, it is difficult to achieve pre-compatibility. The first decade of blockchain is a decade of high-speed development in which new ideas and methods are constantly emerging. Therefore, it may be difficult to implement all the functions defined in the digital assets standard when the existing blockchain is not compatible with the standard protocols.
It is hoped that the digital assets standard can be easily implemented by each blockchain system. If a function is unique to a specific blockchain system, it should not be included in the standard.
After establishing this standard, it is expected to receive increasing support from multiple chains. When blockchain technology is a common feature utilized in mainstream applications, it can speed up assets’ liquidity.
submitted by Floris-Jan to aelfofficial [link] [comments]

Dive Into Tendermint Consensus Protocol (I)

Dive Into Tendermint Consensus Protocol (I)
This article is written by the CoinEx Chain lab. CoinEx Chain is the world’s first public chain exclusively designed for DEX, and will also include a Smart Chain supporting smart contracts and a Privacy Chain protecting users’ privacy.
longcpp @ 20200618
This is Part 1 of the serialized articles aimed to explain the Tendermint consensus protocol in detail.
Part 1. Preliminary of the consensus protocol: security model and PBFT protocol
Part 2. Tendermint consensus protocol illustrated: two-phase voting protocol and the locking and unlocking mechanism
Part 3. Weighted round-robin proposer selection algorithm used in Tendermint project
Any consensus agreement that is ultimately reached is the General Agreement, that is, the majority opinion. The consensus protocol on which the blockchain system operates is no exception. As a distributed system, the blockchain system aims to maintain the validity of the system. Intuitively, the validity of the blockchain system has two meanings: firstly, there is no ambiguity, and secondly, it can process requests to update its status. The former corresponds to the safety requirements of distributed systems, while the latter to the requirements of liveness. The validity of distributed systems is mainly maintained by consensus protocols, considering the multiple nodes and network communication involved in such systems may be unstable, which has brought huge challenges to the design of consensus protocols.

The semi-synchronous network model and Byzantine fault tolerance

Researchers of distributed systems characterize these problems that may occur in nodes and network communications using node failure models and network models. The fail-stop failure in node failure models refers to the situation where the node itself stops running due to configuration errors or other reasons, thus unable to go on with the consensus protocol. This type of failure will not cause side effects on other parts of the distributed system except that the node itself stops running. However, for such distributed systems as the public blockchain, when designing a consensus protocol, we still need to consider the evildoing intended by nodes besides their failure. These incidents are all included in the Byzantine Failure model, which covers all unexpected situations that may occur on the node, for example, passive downtime failures and any deviation intended by the nodes from the consensus protocol. For a better explanation, downtime failures refer to nodes’ passive running halt, and the Byzantine failure to any arbitrary deviation of nodes from the consensus protocol.
Compared with the node failure model which can be roughly divided into the passive and active models, the modeling of network communication is more difficult. The network itself suffers problems of instability and communication delay. Moreover, since all network communication is ultimately completed by the node which may have a downtime failure or a Byzantine failure in itself, it is usually difficult to define whether such failure arises from the node or the network itself when a node does not receive another node's network message. Although the network communication may be affected by many factors, the researchers found that the network model can be classified by the communication delay. For example, the node may fail to send data packages due to the fail-stop failure, and as a result, the corresponding communication delay is unknown and can be any value. According to the concept of communication delay, the network communication model can be divided into the following three categories:
  • The synchronous network model: There is a fixed, known upper bound of delay $\Delta$ in network communication. Under this model, the maximum delay of network communication between two nodes in the network is $\Delta$. Even if there is a malicious node, the communication delay arising therefrom does not exceed $\Delta$.
  • The asynchronous network model: There is an unknown delay in network communication, with the upper bound of the delay known, but the message can still be successfully delivered in the end. Under this model, the network communication delay between two nodes in the network can be any possible value, that is, a malicious node, if any, can arbitrarily extend the communication delay.
  • The semi-synchronous network model: Assume that there is a Global Stabilization Time (GST), before which it is an asynchronous network model and after which, a synchronous network model. In other words, there is a fixed, known upper bound of delay in network communication $\Delta$. A malicious node can delay the GST arbitrarily, and there will be no notification when no GST occurs. Under this model, the delay in the delivery of the message at the time $T$ is $\Delta + max(T, GST)$.
The synchronous network model is the most ideal network environment. Every message sent through the network can be received within a predictable time, but this model cannot reflect the real network communication situation. As in a real network, network failures are inevitable from time to time, causing the failure in the assumption of the synchronous network model. Yet the asynchronous network model goes to the other extreme and cannot reflect the real network situation either. Moreover, according to the FLP (Fischer-Lynch-Paterson) theorem, under this model if there is one node fails, no consensus protocol will reach consensus in a limited time. In contrast, the semi-synchronous network model can better describe the real-world network communication situation: network communication is usually synchronous or may return to normal after a short time. Such an experience must be no stranger to everyone: the web page, which usually gets loaded quite fast, opens slowly every now and then, and you need to try before you know the network is back to normal since there is usually no notification. The peer-to-peer (P2P) network communication, which is widely used in blockchain projects, also makes it possible for a node to send and receive information from multiple network channels. It is unrealistic to keep blocking the network information transmission of a node for a long time. Therefore, all the discussion below is under the semi-synchronous network model.
The design and selection of consensus protocols for public chain networks that allow nodes to dynamically join and leave need to consider possible Byzantine failures. Therefore, the consensus protocol of a public chain network is designed to guarantee the security and liveness of the network under the semi-synchronous network model on the premise of possible Byzantine failure. Researchers of distributed systems point out that to ensure the security and liveness of the system, the consensus protocol itself needs to meet three requirements:
  • Validity: The value reached by honest nodes must be the value proposed by one of them
  • Agreement: All honest nodes must reach consensus on the same value
  • Termination: The honest nodes must eventually reach consensus on a certain value
Validity and agreement can guarantee the security of the distributed system, that is, the honest nodes will never reach a consensus on a random value, and once the consensus is reached, all honest nodes agree on this value. Termination guarantees the liveness of distributed systems. A distributed system unable to reach consensus is useless.

The CAP theorem and Byzantine Generals Problem

In a semi-synchronous network, is it possible to design a Byzantine fault-tolerant consensus protocol that satisfies validity, agreement, and termination? How many Byzantine nodes can a system tolerance? The CAP theorem and Byzantine Generals Problem provide an answer for these two questions and have thus become the basic guidelines for the design of Byzantine fault-tolerant consensus protocols.
Lamport, Shostak, and Pease abstracted the design of the consensus mechanism in the distributed system in 1982 as the Byzantine Generals Problem, which refers to such a situation as described below: several generals each lead the army to fight in the war, and their troops are stationed in different places. The generals must formulate a unified action plan for the victory. However, since the camps are far away from each other, they can only communicate with each other through the communication soldiers, or, in other words, they cannot appear on the same occasion at the same time to reach a consensus. Unfortunately, among the generals, there is a traitor or two who intend to undermine the unified actions of the loyal generals by sending the wrong information, and the communication soldiers cannot send the message to the destination by themselves. It is assumed that each communication soldier can prove the information he has brought comes from a certain general, just as in the case of a real BFT consensus protocol, each node has its public and private keys to establish an encrypted communication channel for each other to ensure that its messages will not be tampered with in the network communication, and the message receiver can also verify the sender of the message based thereon. As already mentioned, any consensus agreement ultimately reached represents the consensus of the majority. In the process of generals communicating with each other for an offensive or retreat, a general also makes decisions based on the majority opinion from the information collected by himself.
According to the research of Lamport et al, if there are 1/3 or more traitors in the node, the generals cannot reach a unified decision. For example, in the following figure, assume there are 3 generals and only 1 traitor. In the figure on the left, suppose that General C is the traitor, and A and B are loyal. If A wants to launch an attack and informs B and C of such intention, yet the traitor C sends a message to B, suggesting what he has received from A is a retreat. In this case, B can't decide as he doesn't know who the traitor is, and the information received is insufficient for him to decide. If A is a traitor, he can send different messages to B and C. Then C faithfully reports to B the information he received. At this moment as B receives conflicting information, he cannot make any decisions. In both cases, even if B had received consistent information, it would be impossible for him to spot the traitor between A and C. Therefore, it is obvious that in both situations shown in the figure below, the honest General B cannot make a choice.
According to this conclusion, when there are $n$ generals with at most $f$ traitors (n≤3f), the generals cannot reach a consensus if $n \leq 3f$; and with $n > 3f$, a consensus can be reached. This conclusion also suggests that when the number of Byzantine failures $f$ exceeds 1/3 of the total number of nodes $n$ in the system $f \ge n/3$ , no consensus will be reached on any consensus protocol among all honest nodes. Only when $f < n/3$, such condition is likely to happen, without loss of generality, and for the subsequent discussion on the consensus protocol, $ n \ge 3f + 1$ by default.
The conclusion reached by Lamport et al. on the Byzantine Generals Problem draws a line between the possible and the impossible in the design of the Byzantine fault tolerance consensus protocol. Within the possible range, how will the consensus protocol be designed? Can both the security and liveness of distributed systems be fully guaranteed? Brewer provided the answer in his CAP theorem in 2000. It indicated that a distributed system requires the following three basic attributes, but any distributed system can only meet two of the three at the same time.
  1. Consistency: When any node responds to the request, it must either provide the latest status information or provide no status information
  2. Availability: Any node in the system must be able to continue reading and writing
  3. Partition Tolerance: The system can tolerate the loss of any number of messages between two nodes and still function normally

https://preview.redd.it/1ozfwk7u7m851.png?width=1400&format=png&auto=webp&s=fdee6318de2cf1c021e636654766a7a0fe7b38b4
A distributed system aims to provide consistent services. Therefore, the consistency attribute requires that the two nodes in the system cannot provide conflicting status information or expired information, which can ensure the security of the distributed system. The availability attribute is to ensure that the system can continuously update its status and guarantee the availability of distributed systems. The partition tolerance attribute is related to the network communication delay, and, under the semi-synchronous network model, it can be the status before GST when the network is in an asynchronous status with an unknown delay in the network communication. In this condition, communicating nodes may not receive information from each other, and the network is thus considered to be in a partitioned status. Partition tolerance requires the distributed system to function normally even in network partitions.
The proof of the CAP theorem can be demonstrated with the following diagram. The curve represents the network partition, and each network has four nodes, distinguished by the numbers 1, 2, 3, and 4. The distributed system stores color information, and all the status information stored by all nodes is blue at first.
  1. Partition tolerance and availability mean the loss of consistency: When node 1 receives a new request in the leftmost image, the status changes to red, the status transition information of node 1 is passed to node 3, and node 3 also updates the status information to red. However, since node 3 and node 4 did not receive the corresponding information due to the network partition, the status information is still blue. At this moment, if the status information is queried through node 2, the blue returned by node 2 is not the latest status of the system, thus losing consistency.
  2. Partition tolerance and consistency mean the loss of availability: In the middle figure, the initial status information of all nodes is blue. When node 1 and node 3 update the status information to red, node 2 and node 4 maintain the outdated information as blue due to network partition. Also when querying status information through node 2, you need to first ask other nodes to make sure you’re in the latest status before returning status information as node 2 needs to follow consistency, but because of the network partition, node 2 cannot receive any information from node 1 or node 3. Then node 2 cannot determine whether it is in the latest status, so it chooses not to return any information, thus depriving the system of availability.
  3. Consistency and availability mean the loss of the partition tolerance: In the right-most figure, the system does not have a network partition at first, and both status updates and queries can go smoothly. However, once a network partition occurs, it degenerates into one of the previous two conditions. It is thus proved that any distributed system cannot have consistency, availability, and partition tolerance all at the same time.

https://preview.redd.it/456x2blv7m851.png?width=1400&format=png&auto=webp&s=550797373145b8fc1471bdde68ed5f8d45adb52b
The discovery of the CAP theorem seems to declare that the aforementioned goals of the consensus protocol is impossible. However, if you’re careful enough, you may find from the above that those are all extreme cases, such as network partitions that cause the failure of information transmission, which could be rare, especially in P2P network. In the second case, the system rarely returns the same information with node 2, and the general practice is to query other nodes and return the latest status as believed after a while, regardless of whether it has received the request information of other nodes. Therefore, although the CAP theorem points out that any distributed system cannot satisfy the three attributes at the same time, it is not a binary choice, as the designer of the consensus protocol can weigh up all the three attributes according to the needs of the distributed system. However, as the communication delay is always involved in the distributed system, one always needs to choose between availability and consistency while ensuring a certain degree of partition tolerance. Specifically, in the second case, it is about the value that node 2 returns: a probably outdated value or no value. Returning the possibly outdated value may violate consistency but guarantees availability; yet returning no value deprives the system of availability but guarantees its consistency. Tendermint consensus protocol to be introduced is consistent in this trade-off. In other words, it will lose availability in some cases.
The genius of Satoshi Nakamoto is that with constraints of the CAP theorem, he managed to reach a reliable Byzantine consensus in a distributed network by combining PoW mechanism, Satoshi Nakamoto consensus, and economic incentives with appropriate parameter configuration. Whether Bitcoin's mechanism design solves the Byzantine Generals Problem has remained a dispute among academicians. Garay, Kiayias, and Leonardos analyzed the link between Bitcoin mechanism design and the Byzantine consensus in detail in their paper The Bitcoin Backbone Protocol: Analysis and Applications. In simple terms, the Satoshi Consensus is a probabilistic Byzantine fault-tolerant consensus protocol that depends on such conditions as the network communication environment and the proportion of malicious nodes' hashrate. When the proportion of malicious nodes’ hashrate does not exceed 1/2 in a good network communication environment, the Satoshi Consensus can reliably solve the Byzantine consensus problem in a distributed environment. However, when the environment turns bad, even with the proportion within 1/2, the Satoshi Consensus may still fail to reach a reliable conclusion on the Byzantine consensus problem. It is worth noting that the quality of the network environment is relative to Bitcoin's block interval. The 10-minute block generation interval of the Bitcoin can ensure that the system is in a good network communication environment in most cases, given the fact that the broadcast time of a block in the distributed network is usually just several seconds. In addition, economic incentives can motivate most nodes to actively comply with the agreement. It is thus considered that with the current Bitcoin network parameter configuration and mechanism design, the Bitcoin mechanism design has reliably solved the Byzantine Consensus problem in the current network environment.

Practical Byzantine Fault Tolerance, PBFT

It is not an easy task to design the Byzantine fault-tolerant consensus protocol in a semi-synchronous network. The first practically usable Byzantine fault-tolerant consensus protocol is the Practical Byzantine Fault Tolerance (PBFT) designed by Castro and Liskov in 1999, the first of its kind with polynomial complexity. For a distributed system with $n$ nodes, the communication complexity is $O(n2$.) Castro and Liskov showed in the paper that by transforming centralized file system into a distributed one using the PBFT protocol, the overwall performance was only slowed down by 3%. In this section we will briefly introduce the PBFT protocol, paving the way for further detailed explanations of the Tendermint protocol and the improvements of the Tendermint protocol.
The PBFT protocol that includes $n=3f+1$ nodes can tolerate up to $f$ Byzantine nodes. In the original paper of PBFT, full connection is required among all the $n$ nodes, that is, any two of the n nodes must be connected. All the nodes of the network jointly maintain the system status through network communication. In the Bitcoin network, a node can participate in or exit the consensus process through hashrate mining at any time, which is managed by the administrator, and the PFBT protocol needs to determine all the participating nodes before the protocol starts. All nodes in the PBFT protocol are divided into two categories, master nodes, and slave nodes. There is only one master node at any time, and all nodes take turns to be the master node. All nodes run in a rotation process called View, in each of which the master node will be reelected. The master node selection algorithm in PBFT is very simple: all nodes become the master node in turn by the index number. In each view, all nodes try to reach a consensus on the system status. It is worth mentioning that in the PBFT protocol, each node has its own digital signature key pair. All sent messages (including request messages from the client) need to be signed to ensure the integrity of the message in the network and the traceability of the message itself. (You can determine who sent a message based on the digital signature).
The following figure shows the basic flow of the PBFT consensus protocol. Assume that the current view’s master node is node 0. Client C initiates a request to the master node 0. After the master node receives the request, it broadcasts the request to all slave nodes that process the request of client C and return the result to the client. After the client receives f+1 identical results from different nodes (based on the signature value), the result can be taken as the final result of the entire operation. Since the system can have at most f Byzantine nodes, at least one of the f+1 results received by the client comes from an honest node, and the security of the consensus protocol guarantees that all honest nodes will reach consensus on the same status. So, the feedback from 1 honest node is enough to confirm that the corresponding request has been processed by the system.

https://preview.redd.it/sz8so5ly7m851.png?width=1400&format=png&auto=webp&s=d472810e76bbc202e91a25ef29a51e109a576554
For the status synchronization of all honest nodes, the PBFT protocol has two constraints on each node: on one hand, all nodes must start from the same status, and on the other, the status transition of all nodes must be definite, that is, given the same status and request, the results after the operation must be the same. Under these two constraints, as long as the entire system agrees on the processing order of all transactions, the status of all honest nodes will be consistent. This is also the main purpose of the PBFT protocol: to reach a consensus on the order of transactions between all nodes, thereby ensuring the security of the entire distributed system. In terms of availability, the PBFT consensus protocol relies on a timeout mechanism to find anomalies in the consensus process and start the View Change protocol in time to try to reach a consensus again.
The figure above shows a simplified workflow of the PBFT protocol. Where C is the client, 0, 1, 2, and 3 represent 4 nodes respectively. Specifically, 0 is the master node of the current view, 1, 2, 3 are slave nodes, and node 3 is faulty. Under normal circumstances, the PBFT consensus protocol reaches consensus on the order of transactions between nodes through a three-phase protocol. These three phases are respectively: Pre-Prepare, Prepare, and Commit:
  • The master node of the pre-preparation node is responsible for assigning the sequence number to the received client request, and broadcasting the message to the slave node. The message contains the hash value of the client request d, the sequence number of the current viewv, the sequence number n assigned by the master node to the request, and the signature information of the master nodesig. The scheme design of the PBFT protocol separates the request transmission from the request sequencing process, and the request transmission is not to be discussed here. The slave node that receives the message accepts the message after confirming the message is legitimate and enter preparation phase. The message in this step checks the basic signature, hash value, current view, and, most importantly, whether the master node has given the same sequence number to other request from the client in the current view.
  • In preparation, the slave node broadcasts the message to all nodes (including itself), indicating that it assigns the sequence number n to the client request with the hash value d under the current view v, with its signaturesig as proof. The node receiving the message will check the correctness of the signature, the matching of the view sequence number, etc., and accept the legitimate message. When the PRE-PREPARE message about a client request (from the main node) received by a node matches with the PREPARE from 2f slave nodes, the system has agreed on the sequence number requested by the client in the current view. This means that 2f+1 nodes in the current view agree with the request sequence number. Since it contains information from at most fmalicious nodes, there are a total of f+1 honest nodes that have agreed with the allocation of the request sequence number. With f malicious nodes, there are a total of 2f+1 honest nodes, so f+1represents the majority of the honest nodes, which is the consensus of the majority mentioned before.
  • After the node (including the master node and the slave node) receives a PRE-PREPARE message requested by the client and 2f PREPARE messages, the message is broadcast across the network and enters the submission phase. This message is used to indicate that the node has observed that the whole network has reached a consensus on the sequence number allocation of the request message from the client. When the node receives 2f+1 COMMIT messages, there are at least f+1 honest nodes, that is, most of the honest nodes have observed that the entire network has reached consensus on the arrangement of sequence numbers of the request message from the client. The node can process the client request and return the execution result to the client at this moment.
Roughly speaking, in the pre-preparation phase, the master node assigns a sequence number to all new client requests. During preparation, all nodes reach consensus on the client request sequence number in this view, while in submission the consistency of the request sequence number of the client in different views is to be guaranteed. In addition, the design of the PBFT protocol itself does not require the request message to be submitted by the assigned sequence number, but out of order. That can improve the efficiency of the implementation of the consensus protocol. Yet, the messages are still processed by the sequence number assigned by the consensus protocol for the consistency of the distributed system.
In the three-phase protocol execution of the PBFT protocol, in addition to maintaining the status information of the distributed system, the node itself also needs to log all kinds of consensus information it receives. The gradual accumulation of logs will consume considerable system resources. Therefore, the PBFT protocol additionally defines checkpoints to help the node deal with garbage collection. You can set a checkpoint every 100 or 1000 sequence numbers according to the request sequence number. After the client request at the checkpoint is executed, the node broadcasts messages throughout the network, indicating that after the node executes the client request with sequence number n, the hash value of the system status is d, and it is vouched by its own signature sig. After 2f+1 matching CHECKPOINT messages (one of which can come from the node itself) are received, most of the honest nodes in the entire network have reached a consensus on the system status after the execution of the client request with the sequence numbern, and then you can clear all relevant log records of client requests with the sequence number less than n. The node needs to save these2f+1 CHECKPOINTmessages as proof of the legitimate status at this moment, and the corresponding checkpoint is called a stable checkpoint.
The three-phase protocol of the PBFT protocol can ensure the consistency of the processing order of the client request, and the checkpoint mechanism is set to help nodes perform garbage collection and further ensures the status consistency of the distributed system, both of which can guarantee the security of the distributed system aforementioned. How is the availability of the distributed system guaranteed? In the semi-synchronous network model, a timeout mechanism is usually introduced, which is related to delays in the network environment. It is assumed that the network delay has a known upper bound after GST. In such condition, an initial value is usually set according to the network condition of the system deployed. In case of a timeout event, besides the corresponding processing flow triggered, additional mechanisms will be activated to readjust the waiting time. For example, an algorithm like TCP's exponential back off can be adopted to adjust the waiting time after a timeout event.
To ensure the availability of the system in the PBFT protocol, a timeout mechanism is also introduced. In addition, due to the potential the Byzantine failure in the master node itself, the PBFT protocol also needs to ensure the security and availability of the system in this case. When the Byzantine failure occurs in the master node, for example, when the slave node does not receive the PRE-PREPARE message or the PRE-PREPARE message sent by the master node from the master node within the time window and is thus determined to be illegitimate, the slave node can broadcast to the entire network, indicating that the node requests to switch to the new view with sequence number v+1. n indicates the request sequence number corresponding to the latest stable checkpoint local to the node, and C is to prove the stable checkpoint 2f+1 legitimate CHECKPOINT messages as aforementioned. After the latest stable checkpoint and before initiating the VIEWCHANGE message, the system may have reached a consensus on the sequence numbers of some request messages in the previous view. To ensure the consistency of these request sequence numbers to be switched in the view, the VIEWCHANGE message needs to carry this kind of the information to the new view, which is also the meaning of the P field in the message. P contains all the client request messages collected at the node with a request sequence number greater than n and the proof that a consensus has been reached on the sequence number in the node: the legitimate PRE-PREPARE message of the request and 2f matching PREPARE messages. When the master node in view v+1 collects 2f+1 VIEWCHANGE messages, it can broadcast the NEW-VIEW message and take the entire system into a new view. For the security of the system in combination with the three-phase protocol of the PBFT protocol, the construction rules of the NEW-VIEW information are designed in a quite complicated way. You can refer to the original paper of PBFT for more details.

https://preview.redd.it/x5efdc908m851.png?width=1400&format=png&auto=webp&s=97b4fd879d0ec668ee0990ea4cadf476167a2948
VIEWCHANGE contains a lot of information. For example, C contains 2f+1 signature information, P contains several signature sets, and each set has 2f+1 signature. At least 2f+1 nodes need to send a VIEWCHANGE message before prompting the system to enter the next new view, and that means, in addition to the complex logic of constructing the information of VIEWCHANGE and NEW-VIEW, the communication complexity of the view conversion protocol is $O(n2$.) Such complexity also limits the PBFT protocol to support only a few nodes, and when there are 100 nodes, it is usually too complex to practically deploy PBFT. It is worth noting that in some materials the communication complexity of the PBFT protocol is inappropriately attributed to the full connection between n nodes. By changing the fully connected network topology to the P2P network topology based on distributed hash tables commonly used in blockchain projects, high communication complexity caused by full connection can be conveniently solved, yet still, it is difficult to improve the communication complexity during the view conversion process. In recent years, researchers have proposed to reduce the amount of communication in this step by adopting aggregate signature scheme. With this technology, 2f+1 signature information can be compressed into one, thereby reducing the communication volume during view change.
submitted by coinexchain to u/coinexchain [link] [comments]

HEX Unique features

HEX is the principal endorsement of store on the blockchain! HEX pays Trustless Interest with no counterparty chance. Given programmable cash the principal program ought to be premium.
Pays holders rather than diggers. Staking HEX resembles getting free mining equipment and power. Bitcoin and HEX correlation
No Satoshi (on the off chance that he doesn't guarantee in 50 weeks) or Mt.Gox dumping on you. No swelling bug conceivable like bitcoin has had. Unit predisposition fixed. Progressively disseminated mining environment. Whale punishment which gives whales coins to stakers, and so forth.
Around 12 million or more of the 18 million all out BTC worth of HEX cases will be given to the stakers on day 353 by shares. What's more, It gets duplicated by the Viral and CriticalMass selection extra multipliers which can build it up to 3x. The offer cost just goes up.
Stakers that end stake early or late compensation faithful stakers. Longer stake submit pays 20% more every year, up to 3x shares, (halfway years are fine). Lower charges, lower swelling. Referral program. Organizer is a showcasing master with a crowd of people. Early adopters get paid amazingly well.
20% Speed reward tumbling to 0% during the fifty weeks. Unclaimed coins paid to stakers 2% every week for 50 weeks. Consistently you don't guarantee, another person gets your coins. Minimum amount and Virality rewards increment payouts to stakers so they make progressively HEX the more individuals that guarantee, than if less individuals asserted, despite the fact that they get unclaimed coins on day 353. Each pumpamental to bolt up supply, increment reception and cost.
Hex has a lower expansion rate than Bitcoin, much after the rate was sliced down the middle twice in its 10 years. The swelling is additionally deferred, in light of the fact that it's just paid on finished stakes, and stakes can most recent 10 years. Failure to exchange staked coins builds the estimation of unstaked coins, and chance that some will early endstake and take care of punishments to faithful stakers.
Trustless Interest.
Suppose you need to make more bitcoin on your bitcoin. What are your alternatives? You could loan your coins out and face the challenge they're not returned, or you could have a go at selling your coins for mining equipment and want to get more coins back later. Bunches of individuals have lost cash attempting either.
Counterparty hazard in Bitcoin ventures.
To acquire enthusiasm on their Bitcoin, most clients send them to a brought together outsider, for example, a trade. There, coins can be acquired to "short" the market. Merchants acquire the coins to sell, in the expectations that they can rebuy them less expensive before they need to return them, along these lines benefitting from value diminishes. These brought together gatherings are security openings that are frequently hacked, annihilate protection, or acquaint expenses on the off chance that you need with get your assets out. Billions of dollars in coins sent to trades or loan specialists have been taken. Not your keys, not your coins.
These concentrated outsiders and brokers are so essential to clients looking for yield (making interest) that the organizations themselves have made more benefit on Bitcoin than its originator. A huge number of dollars of significant worth has moved into the pockets of brokers. HEX fixes this.
This replaces these outsiders with a trustless distributed to framework. Rather than sending your HEX to a trade so they can loan it out for your sake to procure enthusiasm for you, you simply lock it in same brilliant agreement that stamped all the HEX in any case, and it credits you intrigue. In case you're given programmable cash, the principal thing you should program is premium.
HEX pays enthusiasm to stakers rather than excavators.
A few clients take a stab at mining to make more digital money. Rather than sending your cash to a remote super corp to purchase mining gear which appears late, utilized, or never by any stretch of the imagination, you can avoid the deteriorating resource and power bills and simply stake your coins.
HEX is the primary digital currency with a graph of future sellable stockpile (lapsing stakes after some time.) This makes sure about purchasers trust in future estimation of their speculation.
HEX has Speculative Stickiness.
Typical cryptographic forms of money have: Price, hash rate.
HEX has: HEX value, Share cost, Directly influences staker benefit per share: % of supply staking, Average stake length, Average stake size, stake termination diagram after some time, early and late end stake punishments.
HEX links: Website: https://hex.win/ Twitter page: https://twitter.com/HEXCrypto Facebook page: https://www.facebook.com/HEXcrypto Telegram page: https://t.me/HEXcrypto Github: https://github.com/bitcoinHEX Reddit page: https://hexcrypto.reddit.com/ Medium page: https://medium.com/hex-crypto/ Ann: https://bitcointalk.org/index.php?topic=4523610.0
Author information; Bitcointalk username: TridentHorn Bitcointalk profile: https://bitcointalk.org/index.php?topic=4523610.0
submitted by TridentHorn to Cryptocoinworld [link] [comments]

Full Option Koinpro

In today's world of heavily nascent and volatile cryptocurrency, one point or factor stands out. That is exchanges. Cryptocurrency exchanges are sites(whether physical or virtual) where cryptocurrencies are traded for each other or traditional fiat currencies like Euro, Pound Sterling or US Dollar. They may be divided by many criteria, chief of which may be Modus Operandi or Central Control. The Degree of Control suggests a central control of exchange management and resources. There are Centralized, Decentralized and Hybrid exchanges. Now we can narrow down to Centralized Exchanges. These are where transactions are monitored and controlled by the owners of the exchange. Transactions can be made only through mechanisms provided and approved by the central body. Also there is no access to private keys by traders. Examples include Koinpro, Binance, Kucoin, Bittrex etc.
About Koinpro This is a Smart Bitcoin Futures Exchange. KoinPro, your new fangled crypto exchange, that goes beyond crypto and boasts of multiple futures contracts, with its own unique features and benefits. Bitcoin Futures, Contracts for Difference are complex instruments. Trading these financial products carries a high level of risk since leverage can work both to your advantage and disadvantage. There are a lot of exchanges, both crypto and fiat(mainstream and otherwise) trading tools like CFD, oil, futures etc; but not one of them Integrates CFDs like Koinpro. Its a no-brainer choice, since going for KoinPro’s unique double-UP contract, customers can simply enter into a predefined order position that will automatically terminate when the position either gains or loses 100% of its value, or when the contract expires — whichever comes first. insurance coverage is provided as a courtesy to BitGo Prime, which is a sole counterparty Prices derived from a wide range of Tier 1 institutions such as exchanges and professional market makers Trading on a fully non-disclosed basis Fully integrated with BitGo Portfolio & Tax. At KoinPro, we take the safety and security of our clients extremely seriously. To help make KoinPro one of the safest places to trade, we store our customer funds in cold storage wallets provided by BitGo—the world leader in secure digital asset storage. BitGo custody includes a $100 million insurance plan underwritten by Lloyd’s of London—one of the UK’s largest insurance markets.
This insurance coverage is provided as a courtesy to KoinPro users and hence comes at no additional cost. This insurance coverage protects digital assets held by BitGo, Inc. or BitGo Trust Company in the event of;
Third-party hacks or theft of private keys Insider theft by employees of private keys Physical loss or damage of private keys
BitGo has delivered institution-grade security for digital assets since 2013, and features state-of-the-art cold storage technology, which includes a bank-grade Class III vault and stringent controls designed to practically eliminate the risk of loss. Full details about the BitGo custody and insurance protection can be found here.
https://koinpro.com/
https://bitcointalk.org/index.php?topic=5219842
submitted by redoc77 to ICOAnalysis [link] [comments]

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⚡️⚡️BITCOIN ES EL FIN? V343

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